A police constable was killed when an unknown vehicle hit his motorbike while he was returning the outpost, leaving him dead on the spot.The incident took place at Milton Bazar of Kashiyani on Dhaka-Khulna highway in Gopalganj on Tuesday night.The deceased was identified as Obaidur Rahman Mollah, constable of Gopinathpur Police Outpost and son of Mujibur Rahman of Sahmuldi village of the district’s Vanga upazila.Monirul Islam, officer-in-charge of Kashiyani Police Station said, being informed police recovered the body and sent it to Gopalganj General Hospital morgue for autopsy.