MAKHACHKALA, Russia, (AFP) A suicide bomber rammed into a Russian firing range killing five people and wounding scores on Sunday in the volatile North Caucasus region of Dagestan, law enforcement sources said. The explosives-packed car attacked a military base used by the motor rifle brigade at Dalny near the city of Buynaksk, some 40 kilometres west of the local capital Makha-chkala, said the sources, who refused to be identified. Five people are dead. Three of them died on the spot and another two in hospital, a law enforcement source told AFP, adding that the blast had hurt at least another 35 people, two of whom were in critical condition. Russias defence ministry promptly imposed a state of heightened security at military installations in its Southern Military District - made up of the mainly Muslim regions along Russias southern flank. However, it put the death toll from the blast at three and said 33 people were wounded. A heightened security regime has been ordered for the duty officers and guards at all the military installations in the district, ministry spokesman Colonel Alexei Kuznetsov said, quoted by Russian news agencies. He added that the ministry had dispatched a special commission led by the acting Southern Military District commander to the site of the terror attack. When the suicide bomber struck at about 00:30 am (2030 GMT Saturday), guards at the base opened fire on the explosive-laden car and blocked its full-speed accelerations into the centre of the base with a truck, Kuznetsov said. After firing several warning shots, soldiers guarding the field camp opened fire on the terrorists car, he said, quoted by RIA Novosti. The suicide bombers uncontrolled vehicle drove into a military truck that blocked off the entrance to the camp. The blast occurred on the outskirts of the camp, which prevented a larger death toll. The blast was followed by a second roadside explosion that targeted investigators on the way to the scene, but there were no casualties, Russian agencies said.