Hollywood actor Sean Penn interviewed Mexican drug kingpin Joaquin “El Chapo” Guzman at a secret location soon after his jail break.
The interview, conducted in October in the Mexican jungle, is published in Saturday’s edition of Rolling Stone.
Guzman escaped from the maximum security Altiplano jail in July and was recaptured on Friday.
Unnamed Mexican officials say Penn’s secret meeting helped lead them to the fugitive who is back in Altiplano.
Their comments chime with public pronouncements by Attorney General Arely Gomez, who said on Friday that an important aspect of his recapture “was discovering Guzman’s intention to have a biographic film made”.
“He contacted actresses and producers, which was part of one line of investigation.”
In the Rolling Stone article, the result of a seven-hour “sit-down”, Penn and Guzman discuss various topics, including drug trafficking.
Guzman, 58, is quoted as saying: “If there was no consumption, there would be no sales.”
He also rejects responsibility for drug addiction, saying “the day I don’t exist, it’s not going to decrease in any way at all”.
The meeting, apparently arranged by Mexican actress Kate del Castillo, took place in a remote part of Durango state, a Mexican official told Associated Press. Durango borders Sinaloa state, the centre of Guzman’s operations.
A picture of Guzman in Rolling Stone shaking hands with Penn is dated 2 October. Two weeks later, the Mexican authorities reported that the cartel leader narrowly evaded recapture in northwest Mexico and suffered face and leg injuries as he fled.
The authorities said they could have fired on Guzman at his hideout, but decided against because he was with two women and a child.
Another source, quoted by Reuters, said the Mexicans were considering investigating Penn and Castillo.
Mexico meanwhile says it will begin the process of extraditing Guzman to the US, in line with extradition requests from 2014.
Guzman, who was one of the world’s most wanted drug traffickers, escaped from jail through a tunnel dug in the showers.
That was his second escape – he was first arrested in Guatemala in 1993 and escaped from Puente Grande jail in 2001, reportedly in a laundry basket after bribing officials.
He was on the run for 13 years before being held again in 2014. Previous requests from the US have been turned down.
Katy Watson, BBC News, Mexico City
The extradition of “El Chapo” to the US is by no means a foregone conclusion. The two countries have an extradition treaty but there are many steps that need to be taken and officials that need to approve the request.
Many people believe that he should face justice in Mexico first. But the case goes beyond sovereignty and national pride.
Those CCTV images of Guzman slipping down from his prison-cell shower into a mile-long tunnel last year still haunt authorities. He has escaped not just once but twice from high-security prisons and there is concern his influence and financial clout could allow him to do it again.
With the headaches that Guzman has given President Pena Nieto, whose reputation was severely bruised by the escape, perhaps extradition is the safer bet.
No detail was given about the time frame for an extradition but experts say the process could take months.
The attorney general’s office said that lawyers for Guzman would have three days to file objections and 20 more days to prove them, though that timeframe could be extended, AFP news agency reports.
In a statement welcoming Guzman’s recapture, Attorney General Loretta Lynch said Guzman had caused “significant violence, suffering and corruption on multiple continents”.
The US filed requests in 2014 for his extradition so he could face charges of smuggling vast amounts of drugs into the country.
Guzman, who was named Public Enemy Number One by the Chicago Crime Commission in 2013, has been indicted by at least seven US federal district courts.
He was recaptured in the north-western city of Los Mochis in his home state of Sinaloa – which he had come to dominate through his drugs cartel.
During the raid, he managed to flee through a drain but was later caught by marines in a shootout.
Five suspects were killed in the operation and one marine wounded.