Bombs hit rail network

Maoists are known to be active in Bihar

Police in the northern Indian state of Bihar are trying to defuse bombs after a number of trains were derailed.

A series of blasts ripped up stretches of track overnight.

It is suspected Maoist rebels may be to blame, but local authorities are not yet able to confirm responsibility.

Four passenger trains were derailed but no one was injured, a railway official said.

They were all low-speed local trains, Santosh Kumar, a spokesman for the East Central Railway zone, told Reuters news agency.

"We believe that all this has happened due to a strike call by the Maoists," Mr Kumar said.

The rail network in Bihar has been suspended while investigations continue.

The Maoist Communist Centre (MCC) demanded industrial action across the northern region of Bihar on Tuesday after a number of rebel leaders were detained.

The MCC operates a de facto administration in areas where it has strong support.