MEXICO CITY (AP) — Mexican officials on Sunday formally launched the process to extradite drug lord Joaquin “El Chapo” Guzman to the United States, starting what could be a lengthy road full of legal appeals and maneuvering.

Mexican drug lord Joaquin "El Chapo" Guzman is escorted by army soldiers in Mexico City, Friday, Jan. 8, 2016. The world's most wanted drug lord was recaptured by Mexican marines Friday, six months after he fled through a tunnel from a maximum security prison in a made-for-Hollywood escape that deeply embarrassed the government and strained ties with the United States. (AP Photo/Rebecca Blackwell)

Mexican drug lord Joaquin “El Chapo” Guzman is escorted by army soldiers in Mexico City, Friday, Jan. 8, 2016. The world’s most wanted drug lord was recaptured by Mexican marines Friday, six months after he fled through a tunnel from a maximum security prison in a made-for-Hollywood escape that deeply embarrassed the government and strained ties with the United States. (AP Photo/Rebecca Blackwell)

Agents notified Guzman at the maximum-security Altiplano prison where he is being held following his dramatic recapture by Mexican security forces on Friday — six months after he escaped through a tunnel out of the same lockup, embarrassing the government of President Enrique Pena Nieto.

The Attorney General’s Office said in a statement that Guzman was formally informed that he was wanted in the U.S. The notification was done by Mexican agents assigned to the international police agency Interpol, who served two arrest warrants to the drug lord. Guzman’s defense now has three days to present arguments against extradition and 20 days to present supporting evidence, beyond the plethora of other appeals they have already started filing.

Guzman’s powerful Sinaloa cartel smuggles multi-ton shipments of cocaine and marijuana as well as manufacturing and transporting methamphetamines and heroin, mostly to the U.S. He is wanted in various U.S. states and his July 11 escape — his second from a Mexican maximum security prison — strained ties between the countries.

Mexican officials have cautioned that the extradition process might take a while. Guzman’s attorney Juan Pablo Badillo has said the defense has already filed six motions to challenge extradition requests.

On Saturday, a Mexican federal law enforcement official said the quickest Guzman could be extradited would be six months, but even that is not likely because lawyers will file appeals. He said that the appeals are usually turned down, but each one means a judge has to schedule a hearing.

“That can take weeks or months, and that delays the extradition,” he said on condition of anonymity because he was not authorized to comment. “We’ve had cases that take six years.”

Badillo has said that his client shouldn’t be extradited to the U.S. because “our country must respect national sovereignty, the sovereignty of its institutions to impart justice.”

Mexico’s willingness to extradite Guzman is a sharp turnaround from the last time he was captured in 2014, when then-Attorney General Jesus Murillo Karam said the extradition would happen only after he finished his sentence in Mexico in “300 or 400 years.”

Guzman was re-apprehended after a shootout between gunmen and Mexican marines at the home in Los Mochis, a seaside city in Guzman’s home state of Sinaloa. Five suspects were killed and six others arrested. One marine was injured.

Mexican authorities say actor Sean Penn’s contacts with Guzman helped them track the fugitive down — even if he slipped away from an initial raid on the hideout where the Hollywood actor apparently met him.

Penn’s article on Guzman was published late Saturday by Rolling Stone magazine, a day after the drug lord’s recapture.

Penn wrote of elaborate security precautions, but also said that as he flew to Mexico on Oct 2 for the meeting, “I see no spying eyes, but I assume they are there.”

He was apparently right.

A Mexican federal law enforcement official, speaking on condition of anonymity because he was not permitted to comment on the issue, told the Associated Press the Penn interview led authorities to Guzman in the area of Tamazula, a rural part of Durango state.

They raided Guzman’s remote hideout a few days after the interview and narrowly missed capturing Guzman, whose July escape from Mexico’s top security prison — though a mile-long (1.5-kilometer) tunnel — had embarrassed President Enrique Pena Nieto and made his capture a national priority.

Describing the capture, Attorney General Arely Gomez said that investigators had been aided in locating Guzman by documented contacts between his attorneys and “actors and producers” she said were interested in making a film about him, though she did not name them.

Two months after that close call, marines finally caught him in a residential neighborhood of Los Mochis, where they’d been monitoring a suspected safe house. Five people died in a gun battle as troops moved in.

In the interview, Guzman defends his work at the head of the world’s biggest drug trafficking organization, one blamed for thousands of killings. When asked if he is to blame for high addiction rates, he responds: “No, that is false, because the day I don’t exist, it’s not going to decrease in any way at all. Drug trafficking? That’s false.”

Penn wrote that Guzman was interested in having a movie filmed on his life and wanted Mexican actress Kate del Castillo, who had portrayed a drug trafficker in a television series, involved in the project.

“He was interested in seeing the story of his life told on film, but would entrust its telling only to Kate,” wrote Penn, who appears in a photo posted with the interview shaking hands with Guzman.

Penn’s representatives have not commented on claims by Mexican officials.

Associated Press writer Christopher Sherman in Los Mochis, Mark Stevenson in Mexico City and Eric Tucker in Washington contributed to this report.