A level-4 emergency response has been activated in southwest China's Sichuan province over a forest fire that broke out on Friday, according to the provincial emergency management department.

There have been no report of casualties, local authorities said.

A total of 930 people have been dispatched and eight helicopters mobilised to battle the fire that began near Baizi Village, in Yajiang County of Tibetan Autonomous Prefecture of Garze.

Sudden strong winds on Saturday afternoon caused a re-ignition along the eastern front of the fire, which quickly spread over multiple mountain ridges.

Authorities there are investigating the cause of the blaze. (Reporting by Xinhua)