China's state news agency says a fire broke out at an oil refinery in the northeastern coastal city of Dalian Saturday.

It was the second fire at the Dalian refinery since July. Authorities said the flames were extinguished after about six hours without any injuries.

The official Xinhua news agency said the blaze was triggered by a leak in a distillation device at state-run PetroChina's largest refinery Saturday afternoon. PetroChina told Xinhua that the fire had not polluted the air or sea.

Further investigations are under way.