Culiacan, Mexico:
Three prisoners linked to jailed Mexican drug lord Joaquin "El Chapo" Guzman escaped from prison through a tunnel, officials said Thursday.
The men, serving time for drug trafficking and weapons charges, escaped Monday from a prison in Culiacan, capital of the drug-plagued northwestern Sinaloa state, an official of the federal government said, requesting anonymity.
The tunnel was 470 meters (yards) long.
It was dug from the outside in, as there was no evidence of dug-up dirt inside the prison, said the deputy secretary of public security for the state, Hector Castillo Medina.
Sinaloa on the Pacific coast is the home region of many of Mexico's top drug kingpins.
They include Guzman, who led the powerful Sinaloa cartel, a huge exporter of cocaine and marijuana to the United States, until he was captured by navy forces in February.
After Monday's breakout, nine guards at the jail were arrested and another 50 are being investigated as potential accomplices.
The last big-scale escape from a Mexican prison was in 2012, when 132 inmates slipped out of a jail in Coahuila on the border with the United States.