Explosions killed at least 35 people and injured 166 on Friday as workers were repairing a crack in an oil pipeline in the eastern Chinese port of Qingdao, state television said.
The leaking underground pipeline reportedly caught fire and exploded mid-morning while it was under repair, causing extensive damage above ground and allowing oil to spill into the sea nearby, dpa reported.
Online photographs showed paving stones uprooted and several vehicles damaged by the underground blasts.
State broadcaster China Central Television said the toll had risen to 35 dead, with 166 injured, by late afternoon.
Oil covered about 1 square kilometre of Qingdao's Zhaitangdao Road and 3 square kilometres of Jiaozhou Bay, the government's Xinhua news agency quoted officials as saying.
The explosions in the pipeline caused cracks up to 1.5 kilometres long in two roads, the agency said.
The oil also caught fire and exploded on the shore, it said.
The 176-kilometre pipeline belongs to state oil giant Sinopec and runs from Qingdao's Huangdao oil depot to the nearby port city of Weifang.
It opened in late August and was built at a cost of some 1.3 billion yuan (210 million dollars), the agency said.