Rescuers find another body, search for 3 in Mexico oil company blast

A relative leans on a burial chamber during the graveside ceremony for Eva Melchor, a victim of the Mexico oil company office building explosion, in Mexico City, Saturday, Feb. 2, 2013. Melchor died Thursday, in a blast that collapsed the lower floors of Petroleos Mexicanos, or Pemex, headquarters, crushing at least 33 people beneath tons of rubble and injuring 121. (AP Photo/Marco Ugarte) (The Associated Press)

An employee culls through debris searching for office documents amid the rubble left from an office building explosion, in Mexico City, Saturday, Feb. 2, 2013. A Thursday blast collapsed the lower floors of the Mexican state-owned oil company Petroleos Mexicanos, or Pemex, headquarters, crushing at least 33 people beneath tons of rubble and injuring 121. A Pemex spokesman said the floors hit by the explosion housed administrative offices. (AP Photo/Marco Ugarte) (The Associated Press)

Mexico's state-owned oil company says rescuers have found another body amid the rubble of a headquarters building damaged by a still-unexplained blast. The find raises the death toll of Thursday's explosion to 34 people.

Petroleos Mexicanos operations director Carlos Murrieta says rescue crews are still looking for three people in the rubble, and believe they're in the most damaged part of the building.

Officials still have not given any cause for the explosion, though they have said they suspect it was an accident. The blast also injured 121 people.

Rescuers had concluded their search Friday but resumed operations when they suspected more bodies were in the rubble. The latest body was found Saturday, and the news was announced via Twitter by Mexican President Enrique Pena Nieto.