Five children were seriously injured when a bomb exploded in Tanahu district of western Nepal, Army sources said on Tuesday. The explosion occurred when the children were playing with the bomb left by the Maoists, they said.The injured children were aged between 8 and 16.In a separate development, Maoists rebels abducted a local businessman from Nayaroad in Sarlahi district bordering India.Armed Maoists also extorted Rs 7,00,000 from local businessmen of Fidim, the district headquarters of Panchthar district, the Army said.