GUIYANG, Feb. 28 -- A man suspected of starting a bus fire that killed six people was arrested on Friday, police with southwest China's Guizhou Province told Xinhua.

The man, surnamed Su, "took revenge on society" by igniting a barrel of gasoline on the bus, ending in tragedy, said the police source.

The fire was started at around 1 p.m. Thursday as the bus was passing a primary school in the northern part of Guiyang City.

It spread quickly and many people simply did not notice the emergency hammers to smash the bus windows in order to escape, according to survivors.

A four-month-old boy was among the six dead and 35 others were injured.

The injured, including one in critical condition, are being treated at local hospitals.

It is not the first such case in China in recent years. On June 7, 2013, a bus in the east China coastal city of Xiamen burst into flames, leaving 47 people dead and 34 others injured.

On June 5, 2009, a bus in Chengdu caught fire and left 25 passengers dead. Police concluded the fire was deliberately set by an unemployed man who died in the fire.