
Sean Penn unwittingly led Mexican marines to El Chapo after meeting him for an extraordinary interview - and is now under investigation.

The sensational meeting took place deep in the Mexican jungle in October and was arranged by Penn, Mexican actress Kate del Castillo and a fixer, with the permission of the Sinaloa cartel.

El Chapo admitted in the bizarre interview to being the biggest drug trafficker in the world and said he sent engineers to Germany to learn how to build the tunnel he would eventually use to escape a maximum security prison.

The cartel boss was captured on Friday in a daring 4am raid by Mexican marines and was returned to Altiplano jail. The double Oscar-winning actor's meeting with El Chapo led to the gun battle in which he was captured, an official said.

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El Chapo speaks: Sean Penn recounts his secret visit with the most wanted man in the world https://t.co/F4x6x8ANBd pic.twitter.com/8wDb2I6Xkt — Rolling Stone (@RollingStone) January 10, 2016

Locked up: El Chapo, the leader of the Sinaloa cartel, was recaptured six months after he escaped from Mexico's most secure prison

Penn and del Castillo are now under investigation in Mexico.

In an article written by Penn for Rolling Stone, El Chapo says: 'I supply more heroin, methamphetamine, cocaine and marijuana than anybody else in the world. I have a fleet of submarines, airplanes, trucks and boats.'

Despite his notoriety, up until this point the Mexican gangster had always insisted he was 'just a farmer'.

Penn wrote that El Chapo sent engineers - who were already accomplished in tunnel-building from the multitudes of underground paths they have built beneath the U.S.-Mexico border - to Germany to learn how to construct the tunnel he fled down as he escaped from prison in July last year.

The actor claimed the cartel leader was concerned about the low-lying water table beneath the jail.

The Mystic River star said he did not turn El Chapo in because the drug lord's trust 'was not to be f***ed with'.

'I take no pride in keeping secrets that may be perceived as protecting criminals, nor do I have any gloating arrogance at posing for selfies with unknowing security men. But I'm in my rhythm. Everything I say to everyone must be true,' Penn wrote.

It came as:

Scores of people on Twitter called for Sean Penn to be arrested for meeting the world's most wanted drug lord and not turning him in to the authorities;

It was announced El Chapo will fight extradition to the U.S. and his cartel lawyer has already filed six separate injunctions challenging requests to send him to face justice in America - meaning the whole process could take months;

Pictures emerged of the grubby condo where the millionaire was living with his family as fugitives; and

Five suspects were killed in the police raid operation to capture El Chapo and one marine wounded.

In public: Sean Penn was seen at a Help Haiti fundraiser last night with his ex-wife Madonna, despite being under investigation in Mexico

Plotted: The meeting in Mexico was arranged by Penn, Mexican actress Kate del Castillo (pictured with Penn and musicians) and a fixer

Setting it up: Kate del Castillo (pictured) played an integral role in organizing the bizarre interview for Rolling Stone back in October

BIZARRE MOMENTS IN SEAN PENN'S SEVEN-HOUR CHAT WITH EL CHAPO 1. Sean Penn admits he has never learned how to use a laptop computer. 'At 55 years old, I've never learned to use a laptop. Do they still make laptops?' 2. Penn thought his penis might get chopped off. 'D**k in hand, I do consider it among my body parts vulnerable to the knives of irrational narco types, and take a fond last look, before tucking it back into my pants.' 3. Penn has a drunken day dream about a drone. 'I look to the sky and wonder how funny it would be if there were a weaponized drone above us. We are in a clearing, sitting right out in the open. I down the tequila, and the drone goes away.' 4. El Chapo still isn't keen on Donald Trump. 'I mention Trump. El Chapo smiles, ironically saying, "Ah! Mi amigo!"' 5. For some reason, Penn doesn't want to smile in a photograph with El Chapo. 'I explain that, for authentication purposes, it would be best if we are shaking hands, looking into the camera, but not smiling.' 6. Penn compares El Chapo to a superhero for putting on body armor and picking up a gun. 'Following this Clark Kent-into-Superman extravaganza.' 7. Penn offers to snuggle up to an associate of El Chapo. '"Listen, man. You don't have to sleep on that couch. The bed's big. We can talk and cuddle."' 8. Penn's flatulence in front of El Chapo. 'At this moment, I expel a minor traveler's flatulence (sorry), and with it, I experience the same chivalry he'd offered when putting Kate to bed, as he pretends not to notice.' Advertisement

The U.S. has filed at least seven extradition requests in six different states for Joaquin 'El Chapo' Guzman to be extradited but justice officials warned that his lawyers were likely to 'milk it' by firing off different appeals at different stages of the extradition battle to prolong the legal tussle.

El Chapo was caught after contacting actors and directors about making a Narcos-style biopic about his life, Mexican officials said. It is not clear whether Penn was contacted about the movie.

The seeds for the bizarre meeting between Penn and El Chapo were sown back in 2012 after a representative for the Mexican gangster contacted del Castillo, who had posted tweets saying she had more trust in the cartel than the government.

A lawyer for the Sinaloa cartel said flowers were being sent to the actress, however they never arrived.

Del Castillo later met a fixer called Espinoza - and both of them remained in contact with El Chapo's people after his escape.

Penn later met Espinoza and suggested he meet the fugitive for a magazine article and, incredibly, the Sinaloa cartel agreed to it.

Military action: El Chapo was apprehended in an early morning raid in the town of Los Mochis, hundreds of miles from where he met Sean Penn in October and even further from the prison he escaped from in July

El Chapo (left) will fight extradition to the U.S. and his cartel lawyer Juan Pablo Badillo (right) has already filed six separate injunctions challenging requests to send him to face justice in America - meaning the whole process could take months

Badillo and El Chapo go back a long way and first met in 1993. The attorney specializes in fighting extradition and has fought previous U.S. requests for the kingpin to be sent across the border

The drug kingpin, who was wearing a blue tracksuit, was marched into the Mexican attorney general's office before being taken to jail

El Chapo was escorted into a helicopter by Mexican marines - who had their faces covered - who took him to the prison he escaped from

After arriving in Mexico, Penn and his colleagues had all of their electronic items taken away from them by El Chapo's associates and were driven at speeds of over 100mph to an abandoned airstrip.

After boarding a plane, Penn realized his driver had been Alfredo Guzman - El Chapo's son - who would later tell him their aircraft carried scramblers to avoid detection by radar.

Penn revealed that Mexican soldiers waved Alfredo through a military checkpoint and looked 'embarrassed' to have stopped him, showing the cartel's influence and raising questions about the Mexican authorities determination to catch El Chapo.

More than 14 hours after leaving Los Angeles, they finally met the notorious drug lord in a clearing in the depths of the Mexican jungle near the town of Tamazula, Durango, which neighbors his gang's home state of Sinaloa.

The meeting places was around 200 miles from where he was eventually captured in Los Mochis.

Penn wrote that a local family cooked the group enchiladas and tacos before he and El Chapo held seven-hour talks about the cartel boss's life.

Photos have emerged of the condo where Mexico's most notorious drug kingpin, Joaquin 'El Chapo' Guzman, was found during a 4am raid

Pictures reveal the less-than-luxurious surroundings where the millionaire and his family were living as fugitives from Mexican authorities

Inside one of the houses that were searched on the eve by marines special forces during the military operation which resulted in the recapture of Joaquin 'El Chapo' Guzman

A marine stands guard next to a manhole of the sewer system through which the drug kingpin used to try and escape during the raid

Federal forces patrol the perimeter of the Altiplano Federal Penitentiary, where Joaquin 'El Chapo' Guzman has been returned to prison

On patrol: Federal agents and members of the Mexican Army were seen with an armoured vehicle patrol outside the high security prison

Security forces were also seen keeping watch outside a warehouse where a tunnel, connected to the Altiplano Federal Penitentiary, was located and used by the drug lord to escape last year

At one stage they even talked about Donald Trump, to which El Chapo replied: 'Ah! Mi Amigo!'

There were rumors last year that El Chapo had put a bounty on Trump's head after he branded Mexican immigrants 'drug traffickers and rapists'.

The kingpin also claimed he once met Colombian gangster Pablo Escobar, and still sees his own mother fairly often.

Penn also admitted to having a bout of 'traveler's flatulence' in front of El Chapo, who he says ignored it, as well as saying he was wary of having his penis chopped off by 'irrational narco types'.

El Chapo - real name Joaquin Guzman - explained in a video interview how he escaped from the prison and talks of how he became one of the most notorious drug lords of all time.

Speaking to del Castillo, El Chapo explains how he wound up joining the illegal drug trade.

'Well from the age of 15 and on, where I'm from, which is the Municipality of Badiraguato, I was raised on a ranch called La Tuna in that area and up until today there are no job opportunities.

Last July El Chapo tunneled out of his cell in the shower area (pictured) - one of the few places which is not covered by CCTV at the jail

The drugs lord used an adapted motorcycle, which sits on a rail in an underground tunnel, to make his escape from the Altiplano maximum security prison

Authorities discovered the motorcycle, rigged on a special rail system with two metal carts in front of it, which he used to flee through a mile-long long tunnel under the shower space of his prison cell

'Well, its a reality that drugs destroy. Unforunately, as I said, where I grew up there was no other way and ther still isnt a way to survive. No other way to work in our economy to be able to make a living.'

The cartel boss claims he is not to blame for people becoming addicted to drugs, saying people would continue to take narcotics if he died.

Answering questions on whether he his gang is violent, he says: 'Look... all I do is defend myself. Nothing more. But do I start looking for trouble? Never.'

Mexican authorities knew about the meeting between Penn and El Chapo in October and were close to launching a raid on him that month but had to abort it because he was with two women and a child.

The Sinaloa cartel leader was captured on Friday after a daring 4am raid by Mexican marines at a motel in the town of Los Mochis.

He had earlier fled a separate firefight at a house - where five gangsters were killed and another six arrested - with his right-hand man, who was also later apprehended.

Photographs revealed the less-than-luxurious surroundings where the millionaire, along with his beauty queen wife Emma Coronel Aispuro and their children, lived as fugitives from the Mexican authorities.

Children's toys, most likely belonging to his four-year-old twin daughters, were seen scattered across the home. A dead body lies in the corner of a room - a casualty of the police shoot out. Beds were stripped from the police raid and belongings rifled through as forensic teams worked at the crime scene.

El Chapo will fight extradition to the U.S. and his cartel lawyer has already filed six separate injunctions challenging requests to send him to face justice in America - meaning the whole process could take months.

Juan Masini, former U.S. Department of Justice attache at the U.S. Embassy in Mexico, said the extradition process could be drawn out over a period of months.

'They can challenge the judge, challenge the probable cause, challenge the procedure,' he said. 'That's why it can take a long time. They won't challenge everything at once ... they can drip, drip, milk it that way.'

Mexican authorities have confirmed the country is willing to extradite the recaptured drug lord - a total reversal of the government's position after his last capture in 2014.

If the extradition goes ahead, it is likely El Chapo will spent the rest of his life in jail without the possibility of parole.

An official said 'Mexico is ready' for an extradition and 'there are to cooperate with the U.S.' although he warned the legal process could be lengthy and Guzman's attorney is saying he'll battle extradition in the courts.