Four Mexican officials have been charged for being accomplices to the escape of the notorious drugs lord Joaquin "El Chapo" Guzman from a maximum security prison.

Two are members of Mexico's secret service who were based at the prison. The others were control room employees who should have monitored his cell.

They are accused of not raising the alarm once Guzman had escaped.

Guzman escaped in July through a tunnel in his cell that ran 1.5km to a building outside the prison walls.

Guzman's Sinaloa cartel is responsible for much of Mexico's trafficking of drugs to the US.

At least three other people have already been charged in relation to the escape.

The latest charges allege that the four officials did not follow protocols and alert their superiors. Prosecutors add that all the necessary systems needed to sound the alarm were fully functioning.