Mexican state oil company Pemex said on Tuesday all plants at its Salamanca refinery were temporarily stopped due to a power outage.
The company said on its official Twitter (TWTR) page that there was no fire and the incident was under control.
The Salamanca refinery, in central Guanajuato state, is Pemex's fifth biggest, with a daily crude processing capacity of 220,000 barrels.
(Reporting by Ana Isabel Martinez. Editing by Andre Grenon)