The death toll from an explosion at a chemical plant in southeastern Mexico stood at 13 Thursday, with 18 others still missing.
Another 136 people were hurt in the blast Wednesday at the plant in Coatzacoalcos, in Veracruz state.
The cause of the explosion is not immediately known, but Mexican President Enriqie Pena Nieto called it a "tragic accident."
Mexico's state-run oil giant, Pemex, jointly runs the plant with a company called Mexichem. It produces chemicals used to make plastic pipes.
This is the latest in a series of disasters that has plagued Pemex.
A fire at the same plant killed one worker in February, followed by a fire at a Pemex offshore oil platform weeks later, killing two.
A gas explosion and fire at its Mexico City headquarters killed 37 people in 2013.
