Two Mexican lawmakers say at least 18 minutes lapsed before anyone was alerted to the escape of drug lord Joaquin "El Chapo" Guzman.

Deputy Aleida Alavez, who toured the maximum security prison west of Mexico City on Thursday, told The Associated Press that National Security Commissioner Monte Alejandro Rubido said Guzman had an 18-minute head start.

Officials had not said publicly how much time had elapsed from when Mexico's most prized prisoner slipped into a mile-long tunnel Saturday night and when authorities became aware.

An official with the National Security Commission said he would try to confirm the figure, but did not think it was that much time.

Deputy Adriana Gonzalez, who was also on the tour, said personnel monitoring the cameras told her it was about 20 minutes.