The Special Operations Group (SOG) today gunned down ‘‘top commander’’ Ghazi Shahabuddin of the Hizbul Mujahideen, allegedly in a gunfight in Srinagar.Shahabuddin had taken over the Hizbul’s top rank in the Valley following the killing of Riyaz Rasool in January. Meanwhile, six militants were killed in another encounter with Army troops in Bandipora on Thursday, moments after a grenade attack left four security men critically injured.The Hizbul, in a statement released in PoK, said Abdul Rashid Shardar alias Ghazi Shahabuddin, a resident of Pampore in South Kashmir, was killed in custody by the SOG. It alleged the commander was arrested in Sangrama and later killed in custody by the SOG in Srinagar. The outfit has named Ghazi Misbahudin as the new head of its cadre in the state.The police have denied the allegation saying Shahabuddin was trapped in a house in Maharajgunj in Srinagar and killed in a gun battle. The exchange of fire, police say, started in the afternoon after the house, where Shahabuddin was hiding, was sealed off by the police. Two SOG men were injured in the encounter that lasted 30 minutes.‘‘The allegation that he was killed in custody is not correct. He was killed in an encounter with the police and we recovered an AK rifle, its ammunition, a satellite phone and Rs 1 lakh in cash from him,’’ the Director General of Police, Gopal Sharma, said.