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A fire that reduced a tour bus into charred frames on Sunday morning has killed at least 35 people, including two children, in Hunan Province, local authorities said.

A traffic policeman examines an accident site in Yizhang County, central China's Hunan Province, June 26, 2016. A fire that reduced a tour bus into charred frames on Sunday morning has killed at least 35 people, including two children, in Hunan Province, local authorities said. The accident happened at about 10:20 a.m., when the bus crashed into the guardrail on a highway in Yizhang. (Xinhua/Long Hongtao)

The bus was carrying 55 people. Eleven people were hospitalized, including four seriously injured.

The accident happened at around 10:20 a.m., when the bus crashed into the guardrail on a highway in Yizhang. The ensuing oil leak caused the fire, according to the government.

A survivor surnamed Huang said the driver told them the bus door could not open, the driver then escaped from the window next to his seat. Huang smashed a window with a fire extinguisher in order to get out.

Video footage taken by a witness showed that fire and screams engulfed the bus minutes after the crash. Some passengers were seen limping out of the bus covered in blood.

State Councilor Guo Shengkun, who is also public security minister, has ordered all-out efforts to save the injured, identify the cause of the accident, and to take measures to prevent similar tragedies from happening.

A work team headed by Vice Public Security Minister Huang Ming is heading for Hunan to guide the investigation and handling of the accident on site.

The driver has been detained by police.