At least five people were killed on Monday in a suicide attack in the Afghan capital Kabul. The ISIS terrorist group claimed responsibility for the attack on a compound of Afghanistan’s national intelligence agency in Kabul. In Kabul, security officials said the explosion was caused by a suicide bomber who approached the agency’s entrance on foot before blowing himself up. All the casualties reported were of civilian passersby. Najib Danish, a spokesman for the interior ministry, said at least five people had been killed and two wounded. Official put the death toll at six. Danish added that the exact target of the attack was unclear. "The bomber was on foot and detonated his suicide vest on the main road," he said. The blast comes a week after the group claimed an attack on a training facility of the same agency, the National Directorate for Security, in Kabul that ended when the attackers were killed before causing significant casualties. In a statement issued through the group’s Amaq news agency, ISIS said it was also behind Monday’s attack. ISIS’ local affiliate, which first appeared in eastern Afghanistan near the border with Pakistan in early 2015, has become increasingly active and has claimed several recent suicide attacks in Kabul. It has frequently fought Taliban militants and has been heavily targeted by US air strikes and Special Forces operations in its main stronghold in Nangarhar province.