A suicide bomber blew himself up in the Afghan capital of Kabul on Monday, security officials said, but there was no immediate word on casualties. The attacker on foot detonated his bomb close to a police checkpoint near a school in central Kabul, Reuters reported. An Interior Ministry official said many police officials could have been injured. Kabul police spokesman Basir Mujahid said he was about 20m away from the blast near where a demonstration had broken up some 30 minutes before. No militant group has claimed responsibility for the attack that came as hundreds of demonstrators gathered in Kabul to protest against the government’s failure to prevent attacks by Taliban militants in two provinces.