At least three dead after Shanghai bus explosion

This just in, from Xinhua:

At least three people were killed in a bus explosion in Shanghai at about 9:00 a.m. Monday, according to fire fighters who rushed to the scene.

The cause of the explosion is not yet known.

Fire fighters estimated that there were about 50 passengers on board the No. 842 Bus, which suddenly exploded en route between the Guoxing Road and Shunguo Road in Yangpu District, to the northeast of Shanghai.

More (in Chinese) here. Reportedly, more than 20 passengers were injured and taken to Changhai Hospital. A survivor said the back of the bus was on fire.

The cause of the explosion is not yet known.

We will update this post with more information throughout the day.

UPDATE 1, 11:20 am: Here is a map of the accident location. It is just east of Fudan University, not far from the future subway Line 10.

UPDATE 2, 11:45 am: Related? Another Shanghai bus caught fire in March. That fire was also near the back of the bus.

UPDATE 3, 12:53pm: A police spokeswoman tells DPA that it "was not an explosion, but a fire," but an employee of a nearby restaurant said, "I heard a bang, somewhat louder than normal fireworks."

UPDATE 4, 2:21pm: Picture of badly burnt victim here. Not for the faint-hearted. [h/t to dedlam]

UPDATE 5, 2:29pm: More pictures here. [h/t to dedlam]

UPDATE 6, 4:46pm: The bus looks pretty badly burnt up in this latest set of close-up shots from Xinmin (after the jump):