The death toll in an explosion that struck a Mexican oil plant on Wednesday has reached 13 and could rise further.
The blast hit a state facility in the southern city of Coatzacoalcos. The cause of the explosion is unclear.
More than 100 people were injured and thousands had to leave their homes.
Footage showed a large fire and huge plumes of smoke.
The facility is owned by Mexico's state oil company, Pemex. Several explosions have been reported at Pemex facilities in recent years.
Mr Puente tweeted on Thursday: "We have examined the affected area and can say that unfortunately so far there are 13 people dead."
The director of Pemex, Jose Gonzalez Anaya, said in a radio interview that of 136 injured people, 13 were in a critical condition while 48 had been discharged from hospital.
He said the explosion "was caused by a leak" but "we don't know how that leak occurred".
Mr Anaya said the death toll could still rise.
The incident occurred at around 15:15 local time (20:15 GMT) on Wednesday. Veracruz state Governor Javier Duarte told a radio station the blast was felt 10km (six miles) away.
The fire was under control by early evening, Pemex said. Residents were told to stay indoors because of the possible toxic nature of the smoke from the blast, but Pemex said the smoke dissipated quickly, lessening any possible toxic effects.
On Thursday the company said there was no longer any danger from the smoke.
Pemex said the part of the factory hit by the explosion was managed by a sister company, Mexichem.
Associated Press reported that the plant produces vinyl chloride, a dangerous chemical used to make PVC pipes and packaging materials.
Exports of oil from the plant, one of the largest terminals for oil distribution in Mexico, would not be affected, the company added.
In September 2012, an explosion then a fire at a gas plant in the northern state of Tamaulipas killed 33 people.
Pemex's own headquarters in Mexico City was hit by a large gas blast in January 2013, killing 37 people.
A number of fires also struck the company's rigs in the Gulf of Mexico last year, and a worker was killed in another fire at the Veracruz plant in February this year.
