He played for Arsenal for five years between 1997 and 2002, helping the Gunners win the Premier League and FA Cup double in 1998.
The announcement was made by his first club, Red Bull Salzburg, on Thursday.
The Austrian team said in a post on social media: "We mourn our former goalkeeper Alexander Manninger, who tragically lost his life in a traffic accident.
"Our thoughts are with his family and friends. Rest in peace, Alexander."
Manninger also won 33 caps for Austria and was part of the squad for the 2008 Euros held jointly in the country with Switzerland.
He joined the Gunners in a £500,000 move from Grazer AK and made 64 appearances under Arsene Wenger, winning the Premier League and FA Cup during a five-year stay before leaving for Espanyol in Spain.
In tribute, Arsenal wrote on X: "Everyone at Arsenal is shocked and deeply saddened by the tragic passing of former goalkeeper, Alex Manninger.
"All our thoughts are with his family and loved ones at this incredibly sad time. Rest in peace, Alex."
Austrian Football Association (OFB) sporting director Peter Schottel called the keeper "an outstanding ambassador for Austrian football, both on and off the pitch".
He added: "[Manninger] set standards and inspired and influenced many young goalkeepers. His professionalism, composure, and reliability made him an integral part of his teams and the national team.
"His achievements deserve the utmost respect and will be unforgettable. Our thoughts are with his family and loved ones during this difficult time."
The Salzburg Police said its officers were called to a traffic accident involving a train and a car at a level-crossing in Nussdorf am Haunsberg, north of the city, at around 8.20am on Thursday.
Quoting initial investigations, they said the car "was struck and dragged by a train of the Salzburg Local Railway while crossing the tracks. The driver was alone in the vehicle. The train driver was unharmed".
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The railway line was closed, but has since reopened as the accident investigation continues, the force added.
As well as Arsenal, Salzburg and Espanyol, Manninger also played for clubs in Italy, Germany and Spain, including Juventus, Siena, Torino and Augsburg. He won a Serie A title and the Italian Cup while at the Turin giants.
Manninger later returned to the Premier League in 2016, but did not make a competitive appearance for Liverpool after joining on a short-term deal for what proved to be his final season before retiring in 2017.
Juventus celebrated the life of "a man of rare values" in a statement on X saying: "Today is a very sad day. We have lost not only a great athlete, but a man of rare values: humility, dedication and an exceptional sense of professionalism.
"Alex Manninger will be remembered for the example he set, on and off the pitch.
"Juventus expresses its deepest condolences on the passing of Alex Manninger and stands close to his family in this moment of grief."
In total, he made 64 appearances with the Gunners between 1997 and 2002, largely as understudy to David Seaman.
In his first season in north London, the Austrian played in seven Premier League matches and saved a penalty in the FA Cup quarter-final shootout win over West Ham as Arsenal won the double for the second time in the club's history.
Manninger worked as a carpenter before getting his break in football and after retirement, ran his own renovation business in Austria.
The pontiff also criticised those who "manipulate religion and the very name of God" for military and economic gain, on Thursday during a visit to Cameroon.
"The world is being ravaged by a handful of tyrants, yet it is held together by a multitude of supportive brothers and sisters," he said.
The US president responded to the remarks when questioned by reporters outside the White House: "I can disagree with the Pope... I have a right to disagree with the Pope".
He said it was "very important" for the Pope to understand that Iran is a threat to the world. "This is the real world," he added.
Earlier, the Pope addressed the faithful in Cameroon: "Blessed are the peacemakers. But woe to those who manipulate religion and the very name of God for their own military, economic and political gain, dragging that which is sacred into darkness and filth."
He also criticised those who spend billions on "killing and devastation".
"The masters of war pretend not to know that it takes only a moment to destroy, yet often a lifetime is not enough to rebuild," he said.
Pope Leo's swipe at world leaders who are fighting wars came after the US president attacked him for being "WEAK on Crime, and terrible for Foreign Policy".
The Pope has called for peace in the Middle East, igniting a flurry of late-night Truth Social Posts from Mr Trump that criticised the pontiff.
The president said: "We don't like a Pope who says its ok for Iran to have a nuclear weapon."
"We don't want a Pope who says crime is ok in our cities. I'm not a big fan of Pope Leo," he later told reporters.
In response, Pope Leo said he had "no fear of the Trump administration" and his role was not political, adding that he didn't want to "get into a debate" with the US president.
Mr Trump also published an AI generated image on Truth Social that appeared to show him as a Jesus Christ figure.
He later deleted the post following criticism and said: "It's supposed to be me as a doctor making people better."
On his trip to the western Cameroon city of Bamenda, Pope Leo called for peace in the central African country that has been gripped by insurgency violence for more than a decade.
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Speaking at St Joseph Cathedral, the Pope said: "Those who rob your land of its resources generally invest much of the profit in weapons, thus perpetuating an endless cycle of destabilisation and death."
"It is a world turned upside down, an exploitation of God's creation that must be denounced and rejected by every honest conscience," he said.
The conflict in Cameroon's two Anglophone regions is rooted in the country's colonial history, when it was divided between France and Britain after World War I.
English-speaking regions joined French Cameroon in a 1961 vote, but separatists argue they have since been marginalised.
In 2017, English-speaking separatists launched an insurgency with the goal of breaking away from the French-speaking majority and establishing an independent state.
On the eve of Leo's arrival, separatist fighters announced a three-day pause in fighting for the visit.
Metropolitan Police said a lit container was thrown at a premises in Wembley, northwest London, at around 8.30pm on Wednesday.
It is understood the offices of Volant Media, the parent company of Persian news channel Iran International, were targeted.
The container landed in a car park, where the fire extinguished itself, and the suspects fled in a black SUV.
A police armed response vehicle gave chase after the driver failed to stop and the SUV ended up crashing in Ballards Lane in Finchley.
A 19-year-old man and a 21-year-old man were arrested alongside the younger teen on suspicion of arson endangering life
Some nearby buildings were evacuated as a precaution but the attempted arson did not cause any injuries or damage.
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Police said it's not being treated as a terrorist incident, but is being investigated by detectives from Counter Terrorism Policing London.
It is also not currently being linked to recent arson incidents on a synagogue in Finchley and ambulances in Golders Green.
However, the Met said it was aware of claims of responsibility for the attempted arson attacks by the Iran-linked Islamist group Harakat Ashab al-Yamin al-Islamia.
The group, which has claimed other attacks across Europe since the war in Iran began, posted videos on Wednesday on Telegram about the two incidents, according to terror group monitor Site Intelligence.
Benjamin Field had been accused of seducing, defrauding and trying to drive 69-year-old Peter Farquhar to suicide. Farquhar was found dead in his home in the village of Maids Moreton, Buckinghamshire, in October 2015.
Field was jailed for at least 36 years in 2019.
An inquest concluded that Mr Farquhar's death was alcohol-related, with police not treating it as murder until March 2017.
At the murder trial at Oxford Crown Court in 2019, prosecutors claimed Field had driven Mr Farquhar to believe he was losing his mind to inherit his house and money, lacing his food and whisky with tranquilliser drugs to confuse him in the hope that his eventual death would look like suicide or an accident.
Field, the son of a Baptist minister, was a student when he met Mr Farquhar in April 2011 and realised that the university lecturer was conflicted about his homosexuality. The pair eventually started a relationship and got engaged, the trial heard.
Before his murder trial, Field admitted two counts of burglary and three of fraud after fraudulently being in relationships with both Mr Farquhar and his neighbour, fellow pensioner Ann Moore-Martin, as part of a plan to get them to change their wills. Field was cleared of conspiring or attempting to murder Miss Moore-Martin.
After Mr Farquhar's death, Field inherited half his home and bought a flat in Towcester, which he was forced to sell in 2023 to pay compensation to the families of Mr Farquhar and Ms Moore-Martin, who died from natural causes in May 2017.
The Criminal Cases Review Commission referred Mr Field's conviction to the Court of Appeal last year.
Field's lawyer argued at a hearing in March that there was "no evidence" that Mr Farquhar was "forced or deceived" into taking the whisky or medication.
In a ruling on Thursday, three senior judges quashed Field's conviction and ordered a retrial, saying the jurors at trial had "not been properly directed" and the directions given to them on how to reach a verdict were "defective".
Lord Justice Edis said: "The fact that the appellant secretly intended that Mr Farquhar should die did not change the act or, in law, mean that Mr Farquhar's decision to drink whisky was not free, deliberate and informed.
"There was no evidence that the appellant had 'administered' the alcohol."
He continued: "The directions effectively withdrew from the jury the question of whether Mr Farquhar's decision to drink the whisky had been voluntary."
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The judge said that the Crown Prosecution Service should take the "unusual case" to the Supreme Court before any retrial.
Field will remain in prison "for so long as the appeal [to the Supreme Court] is pending", Lord Justice Edis said.
Alongside the life sentence for Mr Farquhar's murder, Field was handed a concurrent 16-year jail sentence for fraud and burglary offences.
The case was the topic of a BBC drama, called The Sixth Commandment, starring Timothy Spall and Eanna Hardwicke.
West Midlands Police said officers were called to Willis Pearson Avenue at around 11.30pm on Wednesday but the victim died at the scene.
A 37-year-old man was arrested on suspicion of being in charge of a dog dangerously out of control and causing injury resulting in death.
He was taken to hospital after his hand was injured in the incident.
Police said the dogs were destroyed at the house due to "continued aggression" when emergency services arrived.
They are not believed to be banned breeds.
The incident follows two other fatal dog attacks last week; a three-month-old girl died in Redcar, near Middlesbrough, and 19-year-old Jamie-Lea Biscoe died after being found with serious injuries in Leaden Roding, Essex.
Deaths from dog bites increased more than 200% in a year, according to a new report on accidental deaths and hospital admissions.