NEW YORK — The secrets of Joaquín "El Chapo" Guzmán's most daring prison escape were revealed Wednesday by a witness who provided the first evidence implicating the accused Mexican drug lord's wife, sons, and brother-in-law in the breakout.

Damaso Lopez Nuñez, a former Guzmán lieutenant, said his boss was determined to escape from Mexico's maximum Altiplano prison, where he was locked after a squad of Mexican Marines captured him in February 2014.

Testifying through a Spanish translator as a prosecution witness, Lopez said Guzmán's wife, Emma Coronel Aispuro, began relaying the boss' instructions during a secret meeting that took place around April 2014 in Culiacán.

Guzmán was "taking the risk ... and thinking of escaping from prison," Lopez said Guzmán's wife told him, the boss' sons and others during the meeting.

During a follow-up session a month or so later, Lopez said Coronel relayed additional instructions from her husband to the plotters: "A tunnel had to be built and they should start to work."

Watching and listening from a courtroom bench, Coronel showed no evident emotion during the testimony as she at times fidgeted with her nearly waist-length dark hair.

She later declined to comment on Lopez's testimony. The U.S. Attorney's Office for the Eastern District of New York similarly declined to comment when asked why Guzmán's wife had not been indicted with her husband on the criminal charges that have him facing a potential life term in prison.

Lopez testified that the group obeyed their leader's relayed instructions.

Guzmán's four adult sons scouted and bought a piece of property near the prison. The site became the starting point for an escape tunnel that was dug beneath the prison, Lopez told jurors.

To guide the tunneling work, Guzmán's team smuggled a global positioning system watch to the boss. Lopez said the watch gave the plotters precise coordinates for Guzmán's prison cell.

Lopez said he oversaw the work. At his boss' instructions, he said he also acquired a warehouse near the property purchased by Guzmán's sons. The effort was funded by $100,000 that Coronel said Guzman had directed to be sent to the plotters, said Lopez.

The tunneling work stretched into 2015. It was also loud. Guzmán later told him he had heard noises "for months" as the digging work got closer to his cell, Lopez testified. Other prison inmates complained about the noise, he told jurors, citing his leader's account.

The concrete below Guzmán's cell "had been very difficult to break through," Lopez testified.

Although prosecutors did not ask Lopez for precise construction details, previous public accounts have said that the tunnel was roughly a mile long and approximately 30 feet below ground. It also had a lighting system.

When the work neared an end, Guzmán relayed instructions that the escape should be scheduled for a weekend. That way, there would be no top officials at the prison.

Despite the tunneling noise and video security cameras in his cell, Guzmán escaped on July 11, 2015, by slipping through an opening in the floor of his shower.

When he climbed down to the tunnel below, Guzmán mounted the back of a small motorcycle driven by an associate, Lopez told jurors.

Emerging at the property bought by his sons, Guzmán transferred to an all-terrain vehicle piloted by his wife's brother, Lopez said. From there, the plotters whisked the boss to a waiting airplane that flew him to the Sinaloa mountains that held many of his hideouts, he added.

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The escape made headline news around the world, catapulting Guzmán to global notoriety. But the alleged drug lord didn't remain free for long.

Mexican authorities recaptured Guzmán on January 8, 2016, near Los Mochis, Sinaloa, following a shootout with Mexican Marines. But he was determined to escape yet again, Lopez told jurors.

Guzmán initially was sent back to the Altiplano prison. However, Mexican authorities later transferred him to another maximum-security lockup in Ciudad Juarez, Lopez testified.

Guzmán relayed a message that he had paid $2 million to a Mexican prison system director in an effort to get a transfer back to the prison where he'd staged the amazing escape. But the transfer never came through, Lopez said.

The alleged drug lord was extradited to the U.S. in January 2017 to stand trial on drug trafficking conspiracy charges.

Challenging Lopez's credibility under cross-examination, defense attorney Eduardo Balarezo focused on the longtime personal relationship between boss and lieutenant.

He referred to earlier testimony in which Lopez said Guzmán was the godfather of his son, while he was the godfather of one of Guzmán's young daughters.

The defense lawyer asked Lopez why he had twice tapped his fist against his chest as he looked toward Guzmán after first entering the courtroom on Tuesday.

"Because I love him," said Lopez.

"And this man you loved so much, this many you spent so much time with, this man whose daughter you baptized, you testified against him, right?" asked Balarezo.

"It's your freedom or his, and you chose yours," the defense attorney added.

I chose to help my family because they have been left adrift," said Lopez. Referring to Guzmán's relatives, with whom he's had an angry falling out, Lopez added: "I'm here because his sons have placed me here."