Maoists blew up a forest office and one person was injured in the blast at Gajapati district in Orissa where the ultras have given a state-wide bandh call on Friday.

A large number of armed Maoists, including women, struck the forest beat office in Paniganda in Adaba area of Gajapati district, about 300 km from here in early hours and dragged out the guard, Inspector-in-Charge of Adaba police station N Kero said.

They blew up the building using powerful explosives after tying the forest guard, he said adding a villager who arrived at the spot out of curiosity after hearing the noise sustained minor injuries.

The incident took place even as a state-wide bandh was observed in protest against ban on CPI (Maoist) and to demand that the arrested Maoists lodged in various jails be treated as political prisoners.

They also alleged that many people had been arrested on false charges and demanded their release. The ultras pasted posters in support of their demands in rural areas of Ganjam, Gajapati and Kandhamal districts, sources said.

Security has been tightened in Naxal-hit districts in southern and western parts to prevent untoward incident. The bandh had little impact in urban centres and evoked mixed response in rural areas amid closure of shops and thin traffic.