The Mexican government offered a $3.8 million reward for the capture of fugitive drug lord Joaquin "El Chapo" Guzman on Monday and sacked top prison officials amid suspicions that guards helped him escape.

Guzman vanished from his cell late on Saturday even though he was wearing a monitoring bracelet and surveillance cameras were trained on the room 24 hours a day, Interior Minister Miguel Angel Osorio Chong said.

Osorio Chong said Guzman "must have counted on the complicity of prison personnel, ... which if confirmed would constitute an act of treason."