New Delhi, Nov 15 : The Islamic State terror group's Khorasan branch or IS-K has claimed responsibility of a blast that struck a bus in Kabul, Khaama Press reported. The explosion took place on November 13 in the capital city's Dasht-e-Barchi area. It was first believed that Afghan journalist Hameed Saighani was among the victims but sources told Khaama Press that Saighani was assassinated in the northern part of Kabul. The IS-K claimed that they planted bombs in the bus that killed 20 people. The claim however was rubbished by Taliban spokesperson Zabiullah Mujahid, saying that only one civilian was killed and three others were wounded. The IS-K is the only terror group that conducts attacks in Afghanistan following the country's takeover by the Taliban on August 15. The Taliban on the other hand has been underrated by the militants and has claimed to have arrested 600 IS-K affiliates in the past three months, the report said. /IANS