At least eight Egyptian policemen were killed in an attack by Islamic State militant group in Cairo on Sunday.The IS group's claim was not independently verified, while the Egyptian authorities were yet to confirm it, Xinhua news agency reported.Egypt's interior ministry said gunmen killed eight policemen in the Helwan district, adding four assailants in a pickup truck intercepted the policemen and showered them with automatic rifle fire.The dead included a lieutenant and seven lower-ranking policemen who were patrolling the area, it said.Anti-security attacks have escalated following the ouster of the Islamist president Mohamed Morsi by the army in response to mass protests against his rule.The Jihadists took from the restive Sinai peninsula a centre for most of their operations.The militants often claim that their attacks were in retaliation for a harsh police crackdown on Islamist supporters of Morsi, which has killed hundreds of protesters and detained thousands.Ansar Beit Al-Maqdes, an affiliate to the Islamic State (IS) in Sinai, has claimed responsibility of most of the attacks.It has been almost a year since last such attack occurred in the region. In June 2015, Militants killed a policeman standing guard outside a museum in Helwan area.The bodies of the victims have been transferred to the Helwan Hospital morgue, and security men still comb the surrounding areas to catch the militants, who escaped the scene, the interior ministry added.IS flag was waving on the assailants' pickup, eyewitnesses said.