Jan. 31, 2013: A blast collapses the lower floors of a building in the headquarters of Mexico's state-owned oil company, crushing at least 33 people beneath tons of rubble and injuring 121. It is being looked at as an accident although all lines of investigation remain open, the head of Petroleos Mexicanos said Friday.
Sep. 18, 2012: An enormous explosion kills 30 workers at a pipeline facility in Reynosa in northern Mexico. Executives say a valve apparently failed as workers performed routine testing where pipelines from gas wells in the Burgos basin converge near the border with Texas. The plant distributes the gas into a processing plant next door that produces fuel for domestic use.
Dec. 19, 2010: A fireball from an illegally tapped pipeline in the central state of Puebla kills 28 civilians, including 13 children.
October 2007: A sudden storm hits an offshore oil rig, killing 22 workers. Three-quarters of them were employed by outside contractors. Poor emergency training is faulted as one of the main causes of those deaths.
Apr. 22, 1993: A series of sewer explosions hit a 50 block-area in Guadalajara. At least 220 people were killed and 300 injured. Investigators later determined the blast was caused by gasoline that had leaked from an underground pipeline into the sewer system.
Nov. 19, 1984: A series of early morning explosions in underground gas pipelines rocks the low-hill valley of San Juan Ixhuatepec, on the northern edge of Mexico City. The blasts devastate one-third of San Juanico, a community of about 250,000, killing 452 people and injuring more than 4,200.
The Associated Press