Mexican authorities searched frantically on Monday for the notorious drug kingpin known as "El Chapo" — but there was no sign of him more than 24 hours after his astonishing, elaborate escape from a maximum-security prison.
In a devastating embarrassment for the Mexican government, the kingpin, Joaquin Guzman, slipped into a shaft through the shower floor of his prison cell and got away in a mile-long, ventilated tunnel outfitted with a motorbike.
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"This is like capturing Osama bin Laden, having him spend a year in prison, and then walking away from that prison only to re-engage in his terrorist activities," said Anthony Coulson, a former supervisor at the U.S. Drug Enforcement Administration.
Former U.S. drug enforcement officials have said they fear that Guzman could quickly retake control of the Sinaloa cartel, which reaches deep into the United States and far around the world.
Intense manhunt underway in MexicoJuly 13, 201503:23
Barry McCaffrey, former director of the U.S. Office of National Drug Control Policy and an NBC News analyst, said Guzman would probably not leave Mexico.
"He's safest there," McCaffrey said on TODAY. "I mean, entire police departments have been bought." But he said that Guzman, through the cartel, represents "a clear threat to our national security."
Guzman escaped prison in a laundry cart in 2001, and he outfitted his safe houses with secret tunnels. He used one of them to escape authorities in February 2014, just before he was caught.
The latest escape raised strong suspicions of corruption inside the prison and humiliated the government of President Enrique Peña Nieto, who campaigned as a cartel-fighter.
"You have to completely renew the Mexican prison system," Luis Miguel Barbosa, a Mexican senator, told reporters on Monday in Paris. "The arrest of all warders and managers is not enough. This happened due to collaboration from within the jail at the highest level."
This story originally appeared on NBCNews.com