Hundreds of Catholic faithful come together Sunday night near Pemex's battered Mexico City skyscraper to pray for the victims of a deadly blast at the site.<br/> <br />The explosion at the oil giant's headquarters killed at least 36 people and injured 121 others.<br/> <br />One more person is still reported missing.<br/> <br />Grieving Pemex employees joined relatives of their colleagues lost in the blast, keeping a united front in the face of tragedy.<br/> <br />(SOUNDBITE) (Spanish) FRANCISCO JAVIER, SAYING:<br/> <br />"My daughter-in-law died. She was in human resources. She died in this blast and I'm here to support my people. Here we were born; here we grew up, all petroleum workers."<br/> <br />Rescue workers had been digging through the last sections of the building's basement and could soon call off their search.<br/> <br />Speculation over the cause of the blast has ranged from a bomb attack, to a gas leak, to a boiler blowing up.<br/> <br />Mexico's government has vowed to find out whether the explosion was a deliberate attack or another stain on the company's poor safety record.
