BEIJING: As many as three people were killed and eight others injured when a bus caught fire during rush hour in China's economic hub Shanghai Monday morning.

About 50 passengers were on board the bus when it suddenly "burst into fire", the shanghai traffic control centre and fire fighters said.

The cause of the fire was not yet known, official Xinhua news agency, which initially reported it was an explosion, it they said.

Three passengers with severe burns were hospitalised, they said, adding, that fire broke out when the bus was moving in the northeast of Shanghai .

An eyewitness said the bus caught fire at 9.15 am (local time) and he saw three people dead and at least eight others injured.