Rescuers were searching stormy Gulf of Mexico seas on Oct 25 for four oil workers still missing after a drilling rig collided with an offshore platform. Two more survivors of Tuesday's collision have been found, as well as another body, bringing the death toll in the mishap to 19, Mexico's state oil company said. Most of the victims drowned after they had abandoned the rig and their life rafts were swamped by high seas. Television footage showed the shattered remains of one orange life boat on a Gulf coast beach, its hard fiberglass shell ripped apart.The failure of the life boats provoked a scandal in Mexico, and legislators called for an investigation into whether they were supplied by a company purportedly linked to the family of former President Vicente Fox's wife, Marta Sahagun. It was unclear whether the boats were defective or had been supplied by the company in question, Oceanografia. But Fox, who is already the subject of a congressional probe of illegal enrichment allegations, quickly issued a statement saying "there is no link between the children of Marta Sahagun and the Oceanografia company." Petroleos Mexicanos director Jesus Reyes Heroles told Mexican senators there would be an investigation of the wreck 20 miles off the coast of Tabasco state during stormy weather that generated 80 mph winds and 25-foot waves. 63 workers have been rescued, some after treading water for hours. It was unclear whether the missing workers were floating at sea or in life rafts. The Mexican navy sent eight helicopters and four boats to help in the rescue effort. Eighty-one workers and five rescue personnel abandoned a subcontractor's drilling rig known as the Usumacinta on Tuesday, after it hit the Kab 101 light-production platform and damaged a valve. President Felipe Calderon, who visited some of the survivors on Oct 25, blamed the weather for the collision, and said he has ordered the navy to continue searching for the missing workers. Pemex said a work crew was at the scene on Thursday evaluating ways to stop the leak at the platform, which the company said was mainly gas and some crude oil, without giving exact estimates. The workers killed included four employees of Petroleos Mexicanos, seven employees of the subcontractor company that operated the rig, at least one rescue-boat crewmember, and six people who worked for other companies, the company said. One woman was among the dead.