Seven workers were reported to have suffered dehydration and physical exhaustion, with another two sustaining minor burns, the Mexican oil company said on Twitter.
“We are working to control and extinguish a fire sustained in a gasoline storage tank at the Ciudad Madero refinery,” Pemex tweeted, adding that both firefighters and the Civil Protection of Cidudad Madero were assisting the operation.
Another 200 people who live near the Ciudad Madero refinery in Tamaulipas state were evacuated, a spokesman for Pemex told Reuters.
The spokesman said that “most of the refinery plants are stopped for security”, while stressing there was a very low risk of the fire spreading to other parts of the facility.
Local television images showed out-of-control flames at the site, where the blaze began during the night in a gasoline storage tank.
The company said firefighters were waiting for the gasoline to burn off, most likely by the afternoon local time, before the fire could be fully extinguished.
The Ciudad Madero refinery is the smallest of Pemex’s six domestic refineries, with a total crude processing capacity of 190,000 barrels per day.