(Updates with reported death toll in first paragraph.)
Jan. 31 (Bloomberg) -- An explosion at the headquarters of Petroleos Mexicanos in Mexico City left 6 people dead, according to radio station Radio Red.
The blast at the so-called B2 building, adjacent to the main tower, injured more than 70 people, Mexico City newspaper El Universal reported on its website.
Milenio TV said people remained trapped under the debris of the damaged building. Hector Serrano, a Mexico City government official, said on his Twitter page that rescue dogs were searching for survivors.
The state oil company said on its Twitter page that the explosion damaged the first and second floors. The incident occurred between 3:30 p.m. and 3:45 p.m. local time and may have been caused by an overheated air conditioning unit, El Universal reported.
At least a dozen ambulances were standing by outside the headquarters as rescue teams searched the damaged building.
Pemex said earlier on its Twitter account that an electrical failure had caused a preventive evacuation of the headquarters complex.
The company hasn’t said how many people were injured or commented on the extent of the damage. A press official for the oil producer confirmed the comments made on Twitter.
According to images shown by Milenio TV, the building’s windows were shattered on several stories of one side while dazed people streamed into the street. Security personnel surrounded the headquarters and roped off the area outside.
Pemex’s headquarters is located in Mexico City’s Miguel Hidalgo borough, a downtown district that includes Chapultepec Park and the National Museum of Anthropology. The main tower, on Marina Nacional Avenue, is the second-tallest building in Mexico.
--With assistance from Nacha Cattan and Eric Martin in Mexico City. Editor: Jose Enrique Arrioja