HANGZHOU, July 6-- A bus fire that injured 32 people in east China's Hangzhou on Saturday was caused by arson, police said on Sunday.

Police have found that the fire was ignited by banana oil, a lacquer thinner. A man seriously injured in the incident is suspected to have been the arsonist. He is being treated in hospital along with 28 others.

The fire broke out at around 5 p.m. on Saturday, when the No.7 line bus carrying 80 people was at a crossing between Dongpo Road and Qingchun Road in the downtown of Hangzhou, capital of east China's Zhejiang Province.

Police have recovered video captured by a CCTV camera on the bus showing a man near the vehicle's back door pouring liquid from his backpack at 5:03 p.m. and using a lighter to set the fire. Flames quickly spread through the bus.

Police also ascertained through the footage that the man, wearing shorts and slippers, got on the bus at the terminal station of Lingyin Temple at 4:09 p.m. Police are still verifying the suspect's identity.

Lingyin Temple is a famous tourist attraction in the scenic city, known for its picturesque West Lake. Investigators said that many of the passengers aboard the bus were tourists from five provinces and cities outside Hangzhou. There are three minors among the injured.

A source with the Hangzhou Public Security Bureau told Xinhua on Saturday that police have not found any clues suggesting the incident was related to terrorism.

Witnesses said drivers of nearby private cars took out their extinguishers to join efforts to put out the bus fire. Passengers on the burning vehicle rushed out after its front door opened. Some smashed window glass to escape.