Mexico hunts for escaped drug lord

Mexican authorities continue their hunt for drug kingpin Joaquin "El Chapo" Guzman as investigations focus on whether he had inside help to escape through a tunnel beneath his prison cell.

The break-out, the second from maximum security for the head of the powerful Sinaloa cartel in the past 14 years, is being viewed as a personal embarrassment for President Enrique Pena Nieto whose government won praise for bringing Guzman to brook in February last year.

Troops and police were deployed to find the diminutive drug lord after he vanished late Saturday from the Altiplano prison, 90km west of Mexico City, after 17 months behind bars.

Prosecutors had since been questioning about 30 prison employees of various ranks, including the warden, federal officials said on Sunday.

On a state visit to Paris, Pena Nieto said Guzman's flight was "an affront to the state" and demanded an investigation into whether his guards helped him.

Guzman was able to slip out even though surveillance cameras were trained on his cell.

A hole 10 metres deep with a ladder in it was discovered when he failed to return from taking a shower.

The gap led to a 1.5-kilometre long tunnel with a ventilation and light system apparently dug with the help of a motorcycle mounted on a rail to transport tools and remove earth.

The tunnel led to a grey brick building on a hill surrounded by pastures in central Mexico State.

Prosecutors have released a video showing the hole inside the building's dirt-covered floor. A bed and kitchen were in the facility, indicating people may have lived there.

As investigators tried to figure out how Guzman absconded again, police and troops manned checkpoints and searched cars and trucks on nearby roads.

"If he's not captured in the next 48 hours, he will have completely regained control of the Sinaloa cartel," retired US Drug Enforcement Administration operations chief Mike Vigil told news agency AFP on Sunday.

"If he is able to make his way to Sinaloa, his native state, and gets into that mountainous range, it's going to be very difficult to capture him because he enjoys the protection of local villagers."

Several states, including Sinaloa, set up checkpoints on roads. Central Puebla state said it was using X-ray technology at toll booths to see through cars.

Troops in Guatemala launched a special operation at the border with Mexico. It was in that country that Guzman was first arrested in 1993.

His first escape was in 2001, when he slipped past authorities by hiding in a laundry cart in western Jalisco state.

Marines recaptured him in February 2014 in a pre-dawn raid in a condo in Mazatlan, a Pacific resort in Sinaloa state, with the DEA's help.

He was then jailed at Altiplano, which houses several other infamous drug capos captured during Pena Nieto's administration.

Authorities had already investigated a strange prison visit to Guzman in March, when a woman managed to see him by using a fake ID to enter the facility.