Four policemen, including two sub-inspectors, were killed and seven others injured in an encounter with Maoists in Narayanpur district of south Chhattisgarh on Wednesday.“An encounter took place between the police and Maoists near Irapanar village in Abujhmad area of Narayanpur today. Two police sub-inspectors and two constables lost their lives [in the encounter]. Seven jawans were injured and are being brought to Raipur [for treatment],” Devnath, Additional Inspector General of the Anti-Naxal Operation (ANO) unit of Chhattisgarh police said.According to D. M. Awasthi, special Director General of Police in charge of the ANO, the encounter took place when the police team was venturing into the core Maoist area of Abujmad.Exchange of fire for over an hour“The operation was planned by Narayanpur SP [Superintendent of Police]. The police party left the base camp on Tuesday evening. The exchange of fire between the Maoists and the police team went on for over an hour,” he said.In another incident, two policemen suffered injuries in an IED (Improvised Explosive Device) explosion in Bijapur district of south Chhattisgarh.The IED, planted by Maoists, exploded when a police team was carrying out a search operation in Basaguda area of Bijapur. The injured policemen were evacuated to Raipur by a chopper.