Some of the passengers were feared to have been killed and buried under the branches of the huge tree which was demolished because of the collision, sources said.
Rescue operation was on.
The injured were admitted to a government hospital in Siwan.
Siwan: Four persons were on Saturday killed and twelve others injured when a speeding bus rammed into a roadside tree on Gopalganj-Siwan national highway near Siwan in Bihar, official sources said.
First Published: Saturday, August 04, 2012, 17:32