MEXICO CITY — An explosion killed 13 people and injured scores at a petrochemical plant on Mexico's southern Gulf coast, forcing evacuations as a fire billowed a huge toxin-filled cloud into the air.
The head of Mexico's civil defense agency, Luis Felipe Puente, wrote in his Twitter account Thursday that emergency personnel had been able to enter the burned-out plant and found 10 more cadavers. Three workers had been reported dead immediately following the blast Wednesday afternoon.
The state oil company, Petroleos Mexicanos, said 136 workers had been hurt in the blast in the industrial port city of Coatzacoalcos. Eighty-eight of the injured remained hospitalized.
The director of Petroleos Mexicanos told the Radio Formula station that 13 of the injured were in serious condition, and said the death toll could rise.
Jose Antonio Gonzalez Anaya said the blast "was caused by a leak. ... We don't know how that leak occurred."
Veracruz state Gov. Javier Duarte earlier told Radio Formula that the blast was felt as far as 6 miles (10 kilometers) away, adding that more than 2,000 people were evacuated from the area as a precaution.
Pemex reported the fire under control late Wednesday, but initially urged people to stay away from the area as a precaution.
"The cloud that emanated from the PMV plant in Coatzacoalcos is dissipating rapidly, which means it is losing its toxic effects," it said via its Twitter account.
The company later said there was no longer any danger to people nearby. Still, local officials canceled classes at area schools for Thursday.
Pemex said explosion occurred in the Clorados 3 plant of Petroquimica Mexicana de Vinilo. It said the plant is operated by another company, Mexichem, in partnership with Pemex. The plant produces vinyl chloride, a hazardous industrial chemical that is used to make PVC pipes and for other purposes.
The Veracruz state Health Department said in a statement that two patients were in grave condition Wednesday night from burns to their air passages from toxic gases. Others were treated for minor burns, contusions and broken bones.
There have been a number of accidents in recent years at facilities owned by Pemex or where it operates. In early February, a fire killed a worker at the same facility. Also in February, two people were killed and eight injured in a fire on an offshore Pemex platform in the Gulf of Mexico.