Mexico’s top immigration official will face criminal charges over a fire that killed 40 migrants in Ciudad Juarez last month.
Federal prosecutors said Francisco Garduno was remiss in not preventing the disaster despite earlier indications of problems at his agency’s detention centres.
The decision to file charges against the head of the National Immigration Institute was announced late on Tuesday by the federal Attorney General’s Office.
It followed repeated calls from within Mexico, and from some Central American nations, not to stop the case at five low-level officials, guards and a Venezuelan migrant already facing homicide charges.
“We are going to wait and we are going to make decisions in the (right) moment,” Mr Lopez Obrador said.
Anger initially focused on two guards who were seen fleeing the March 27 fire, without unlocking the cell door to allow the migrants to escape, but Mr Lopez Obrador said earlier on Tuesday that they did not have the keys.
The Attorney General’s Office said several other officers of Garduno’s agency will also face charges for failing to carry out their duties, the statement said, but prosecutors did not explain what charges or identify the officials.
Prosecutors said the case showed a “pattern of irresponsibility”.
There have long been complaints about corruption and bad conditions at Mexico’s migrant detention facilities, but they have never been seriously addressed.
Mr Lopez Obrador’s comments about the guards in last month’s fire in the border city of Ciudad Juarez came on the day the bodies of 17 Guatemalan migrants and six Hondurans killed in the fire were flown back to their home countries.
It was unclear what effect Mr Lopez Obrador’s comments might have on the trial of the guards, who were detained previously over the fire.
“The door was closed, because the person who had the keys wasn’t there,” he said.
A video from a security camera inside the facility shows guards walking away when the fire started inside the cell holding migrants.
The guards are seen hurrying away as smoke fills the facility, and they do not appear to make any effort to release the migrants.
Three Mexican immigration officials, a guard and a Venezuelan migrant are being held for investigation in connection with the fire. They face homicide charges.
The migrant allegedly set fire to foam mattresses at the detention centre to protest about what he apparently thought were plans to move or deport the migrants.