Bhubaneswar, July 17 - Maoist rebels shot dead a policeman and killed a paramilitary trooper in a landmine blast in two separate incidents in Orissa's Sundergarh district, police said Friday.

'The Maoists killed a police sub inspector and a constable of the Central Reserve Police Force (CRPF) Thursday,' Inspector General Pranabindu Acharya told IANS on phone.

He said the Maoists looted a private vehicle, which was loaded with explosives meant for mining activities and was on its way to Koida town from the steel city of Rourkela, after opening fire on its driver Thursday night.

The rebels then fired indiscriminately at a police van nearby and abducted sub inspector Ajit Bardhan, he said. After shifting the explosives to a place bordering Jharkhand, the rebels set fire to the vehicle and shot Bardhan dead.

Soon after the van was looted, the CRPF along with police launched a combing operation in the area during which one trooper was hurt in a landmine explosion. He succumbed to his injuries on the way to hospital, Acharya said.

The steel city of Rourkela is located about 500 km from state capital Bhubaneswar.