9 in police custody after E China oil pipeline blasts

An excavator is used at the site of a pipeline explosion in Qingdao Development Zone, in Qingdao, east China's Shandong Province, Nov. 24, 2013. A leaking pipeline caught fire and exploded on Friday morning in Huangdao District of Qingdao. (Xinhua/Li Ziheng)

Nine people have been put in police custody after oil pipeline leakage and blasts killed 55 people in east China's coastal city of Qingdao, police said Tuesday.

Seven of them are from Sinopec, the country's largest oil refinery which owns the pipeline, and two from the city's economic and technological development zone, said the police investigating the accident.

The blasts on Friday also left nine people missing and injured more than 160 others.