Special forces have killed at least five gunmen in a special operation near Makhachkala, the capital of Russia’s North Caucasus republic of Dagestan, a Russian security source said here Friday.The source added that six elements of the special forces were injured during the shootout when they stormed a house where the gummen holed up. Engineers are now examining the house where the gunmen holed up. A group of investigators has arrived at the scene.According to initial information, some of the militants may be involved in assassination of former interior minister of Dagestan Adel Garaa Mohammed Tahirov .Earlier Thursday a special task police officer was killed and his two colleague were wounded in the village of Semender ,” a law-enforcement source told Itar-Tass .The operation was conducted in Semender in Makhachkala’s northern suburb. Police blocked a house where militants had been hiding. The republic’s operations headquarters announced the regime of antiterrorist operation in the area.The counterterrorism operation in Semender began early on Wednesday, after security forces entered the village to search for , a suspected member of an illegal armed group