Police have detained seven employees of China's largest oil refiner, Sinopec, following last week's oil pipeline blast that killed at least 55 people…Two Qingdao city employees also were in police custody…The Sinopec pipeline…ruptured…and spilled oil along a long stretch of road, as well as into the nearby sea. Hours later the oil exploded as workers tried to clean up the spill. China's government demanded accountability in the disaster, the deadliest involving Sinopec. Yang Dongliang, head of the State Administration of Work Safety…said the pipeline's layout was unreasonable, that its safety management was lax and that Sinopec and local officials failed to take enough preventative measures after the leak, such as cordoning off the area and evacuating residents…[The] blast also left 136 people injured and nine others missing. Sinopec's expansion of petrochemical projects has met with resistance from…the public…Sinopec apologized…for the explosions. It said it would investigate and "give timely reports."