MEXICO CITY (February 1, 2013)—The death toll from an explosion at the headquarters of Mexico’s state-owned oil company has risen to 32 people, the company’s director said Friday.

Emilio Lozoya said 121 people were treated for injuries after Thursday's blast in an auxiliary building at the headquarters of Petroleos Mexicanos, beside the iconic 51-story Pemex tower.

He said Friday that rescue efforts continue and people still could be trapped.

About 1,700 people work in the building that was affected, including as many as 250 employees in the first four floors affected by the blast.