At least 30 firefighters sent to tackle a forest blaze in remote mountains of southwest province killed.

At least 27 firefighters have died after they were sent to tackle a forest blaze in remote mountains in southwest China’s Sichuan province at the weekend, authorities said on Monday.

The deaths occurred after a change of wind on Sunday as the firefighters were battling the blaze in a rugged area at an altitude of 3,800 metres, according to the Ministry of Emergency Management and the military.

The ministry said three local residents recruited to help fight the blaze also died.

Nearly 700 people were battling the fire in Sichuan’s Muli county that erupted on Saturday, but contact was lost on Sunday with the 30. Two helicopters carrying medical staff and military personnel were dispatched to help in the search.

China has been battling forest fires in recent weeks in various parts of the vast country, including on the outskirts of Beijing, fed by dry weather and high winds across many northern areas.

The death toll among the firefighters appeared to be the worst since 2015, when an explosion at a chemical warehouse in the port city of Tianjin killed 173 people, most of them firefighters and other first responders.

That blast was blamed on illegal construction and unsafe storage of volatile materials.

Scores of workers have also died in recent industrial accidents, including 85 in a pair of explosions last month.