A policeman was killed and two others were injured today when suspected Naxalites opened fire at their vehicle near Tatijharia, about 40 km from Hazaribagh. Additional Superintendent of Police (ASP) Kuldeep Dewedi, posted at Giridh, said the policemen were going to Ranchi from Giridih to fetch some articles when they came under fire. The ASP said the policemen also retaliated. He said the two injured were admitted to a hospital at Meru, near Giridih.