BEIJING (Reuters) - Firefighters are struggling to douse a forest fire that broke out in the mountains of southwestern China at the weekend and killed 30 firefighters, state media said on Monday.

The fire broke out on Saturday in the Muli county of Sichuan province, perched at an altitude of more than 4,000 m. (13,000 ft), with poor transport and communication links.

Images broadcast by state media showed flames and thick white smoke rising from a mountainside. It was not immediately clear whether there were any civilian casualties.

By Sunday afternoon, authorities had sent nearly 700 firefighters to put out the fire, but 30 of them went missing after a surge of flames fed by a sudden shift in the wind, state media said.

All the missing fighters were confirmed dead on Monday, state television said, adding that their bodies had been retrieved.