An oil pipeline exploded Friday in eastern China, killing at least 22 people, the state-run news agency Xinhua reported.

Authorities were still trying to determine the number of those injured, after the pipeline caught fire near the port city of Qingdao, about 300 miles north of Shanghai.

The oil line sprung a leak in the pre-dawn hours, Xinhua said, citing the city government. The oil flow was cut off, and workers went out to repair the breach. The explosion occurred in the late morning.

The pipeline, which is 176 kilometers (109 miles) long, belongs to Chinese petroleum giant Sinopec and connects the oil port to chemical plants further inland.

Maritime authorities are checking the coastline for possible oil leaks, Xinhua said. None have been reported so far.