Maoists blew up a Block Office building in Malkangiri district early today. Official sources said, over 50 heavily armed rebels stormed into Padia under Kalimela police station area, about 70 km from Malkangiri and triggered a landmine explosion to blow up the Block Office building. After blasting the newly constructed building, the ultras disappeared into the nearby forest raising slogans against anti-naxal operations by the security forces. The ultras had recently blown up the police outpost at Padia. Over a dozen buildings including village panchayat offices, godowns and schools have been destroyed by the Maoists so far this year.