The leader of the Jalisco New Generation Cartel, whose real name is Nemesio Rubén Oseguera Cervantes, died on Sunday, the Associated Press reported.
An official, who requested anonymity because they were not authorised to speak publicly, told the news agency the military operation was carried out in the western state of Jalisco.
It followed several hours of roadblocks with burning vehicles in Jalisco and other states. Such tactics are commonly used by the cartels to block military operations.
The US State Department had offered a reward of up to $15m for information leading to the arrest of El Mencho. In February, the Trump administration designated the cartel as a foreign terrorist organisation.
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The US president threatened, at one point, to take the Arctic island by force in the interests of "national security".
However, in late January he announced "the framework of a future deal" on Greenland and its security following talks with NATO secretary general Mark Rutte.
Now, Mr Trump has claimed he is sending a boat to "take care of the many people who are sick" in Greenland, which has a universal public healthcare system.
He announced the plan at a dinner for Republican governors at the White House.
Mr Trump posted on Truth Social: "Working with the fantastic Governor of Louisiana, Jeff Landry, we are going to send a great hospital boat to Greenland to take care of the many people who are sick, and not being taken care of there. It's on the way!!!"
Louisiana Governor Jeff Landry reposted Mr Trump's message on X - and added: "Thank you, President [Trump]! Proud to work with you on this important issue!"
The US Navy has two hospital ships, the Mercy and the Comfort, which support forces on deployments and provide disaster and humanitarian relief.
The White House and Mr Landry's office have not made any further comment on the post - or revealed whether the ship had been requested by Denmark or Greenland.
Denmark's prime minister, Mette Frederiksen, said in a Facebook post on Sunday that she was "happy to live in a country where there is free and equal access to health for all. Where it's not insurance and wealth that determine whether you get proper treatment".
"You have the same approach in Greenland."
Aaja Chemnitz, one of the two Greenlandic politicians in the Danish parliament, wrote on Facebook: "Donald Trump wants to send a hospital ship to Greenland.
"It seems rather desperate, and does not contribute to the permanent and sustainable strengthening of the healthcare system that we need."
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Denmark maintains control of the territory's foreign affairs and defence.
Troels Lund Poulsen, the country's defence minister, told Danish broadcaster DR on Sunday that the ship was not needed.
"The Greenlandic population receives the healthcare it needs," said Mr Poulsen.
Mr Trump's post came hours after Denmark's Joint Arctic Command said it had evacuated a crew member of a US submarine off the coast of Greenland after the person needed medical treatment.
The submariner was retrieved by a Danish Seahawk helicopter that had been deployed on an inspection ship.
Pro-and anti-regime activists protested at five universities in Tehran on Saturday, in some instances facing off against each other.
At the Ferdowsi University in Mashhad, Iran's second city and birthplace of Ayatollah Khamenei, video shows a large gathering of anti-regime protestors chanting "so much crime all these years" and "death to this rule".
These demonstrations are nowhere near the scale of the protests six weeks ago which saw uprisings in towns and cities across all Iran's 31 provinces, but it is brave to be coming out at all given the authorities' crackdown in January.
The numbers killed then are still unclear, but the US-based Human Rights Activists Agency (HRANA) says they have verified at least 7,015 fatalities and have thousands more cases under review.
The government has admitted to 3,117 deaths including around 200 security personnel. Donald Trump has said he believes 32,000 people were killed.
The 40th day is an important moment in the mourning process in Iran. During the revolution in 1979, 40th day commemorations became flashpoints for fresh protest, sparking renewed crackdowns and killings and further cycles of unrest. As a result, the Iranian regime has been wary of allowing mourners to gather for commemorative rituals.
Last week, clashes around the 40th day took place in Abdanan, a city near the border with Iraq. Videos show people chanting "death to Khamenei" as they remembered Alireza Seydi, a 16-year-old boy killed on January 8th. In another video from the city, the sound of gunfire echoes across the valley.
It is difficult to tell what exactly the response of the authorities has been to this latest unrest. Internet is back but it is patchy.
On Tuesday, the Ayatollah gave a speech saying some of those who took part in the January protests had been "naive and inexperienced" and were deceived by the rioters, but that they were still "part of us, they were our children".
Given the US military build-up across the Middle East, the Iranian authorities appear not to want to provoke Donald Trump by being heavy-handed with protesters - but, instead, to focus minds on further negotiations on Iran's nuclear programme which they say could take place next week.
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They are signalling that they are prepared to work towards a deal but that they stand ready to fight should the US strike.
Now it is up to Donald Trump to decide whether and how long he is prepared to wait for a deal, and what he does if he fails to get one.
In each episode of the new long-form series, our reporter Olive Enokido-Lineham will break down one topic and get to the context behind the story.
She'll be speaking to our correspondents from around the world and experts on that particular topic.
Watch our full episode at the top of this article.
Before re-launching Sky News Explains, Olive specialised in verification and open-source investigations (OSINT). Her stories include investigations into the war in Gaza, to verifying videos from Ukraine and Syria.
Olive also produced the Sky News documentary Escaping Putin, which follows a Russian soldier who fled from the army and the anti-war activists behind it.
For the first episode of Sky News Explains, Olive looks at how Donald Trump reinvented the US immigration agency ICE.
ICE has been in the news for months, but the agency itself is over 20 years old. Olive looks at who ICE are, how their tactics have changed and why Trump has given them so much money and power.
In the episode, Olive analyses footage of ICE agents and data. She talks to former ICE acting director John Sandweg, and two of our US correspondents Mark Stone, in Washington DC and Martha Kelner - who reported from Minneapolis following the shooting of Renee Good.
Corporal Lucy Wilde, 25, who documented her fitness routines and daily life on the social media platform, was reportedly found dead at her barracks in Warminster, Wiltshire, on 5 February.
The Prince of Wales, colonel of the Welsh Guards, was struck by the "warmth and compassion" of Cpl Wilde, of the Royal Yorkshire Regiment, when he met her in 2024.
"It was with immense sadness that I learned of Cpl Lucy Wilde's death," said the prince. "I remember our meeting during her time with the Welsh Guards, where her warmth and compassion were unmistakable."
"She served with courage and distinction as a medic and sought always to help others. I send my heartfelt condolences to her family and friends."
The Ministry of Defence said the circumstances surrounding Cpl Wilde's death were being investigated, it was reported.
Cpl Wilde was previously attached to the Welsh Guards. In a statement, the regiment said: "It is with deep sadness that the Welsh Guards mark the passing of Corporal Lucy Wilde.
"Lucy was attached to the battalion until Christmas, before moving on to her next posting with the 2nd Battalion, Royal Yorkshire Regiment.
"In the short time she spent with us, she quickly became part of the Welsh Guards family - not just as an exceptional medic, but through the bonds of friendship she formed in the Welsh Guards, along with the warmth, humour and professionalism she brought to all who worked with her.
"She was known for her calmness under pressure, tireless care for others, and unwavering commitment to her role."
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Cpl Wilde was commended after being first on the scene of a "mass casualty" incident in the Falklands when a vehicle overturned, injuring a number of Welsh Guards.
"Lucy was first on the scene, and worked relentlessly to treat casualties and ensure every Guardsman was accounted for and safe," the statement added.
"Her actions that day were nothing short of outstanding, and she was rightly commended for her courage and professionalism.
"Lucy had a rare ability to lift those around her. She was popular, genuine and deeply respected. Her loss is felt across the battalion and far beyond."