A suicide bomber killed at least nine people and wounded 12 in an attack on a police base in Kabul on Monday, an Afghan official said. Kabul police spokesman Basir Mujahid said the attacker joined a line of people waiting to enter the local headquarters of a branch of the national police after having lunch and praying outside. The bomber detonated his payload after being spotted near the gate. [related-post] "Unfortunately the majority of the killed and wounded are civilians,'' Mujahid said, adding that two police officers were among the dead and a third was wounded. The attack targeted the Afghan National Civil Order Police, a militarized force that often fights on the front lines of the war with the Taliban. The attack took place in a busy part of western Kabul, near the zoo. Officials had initially said the explosion was caused by a suicide car bomb. The Taliban claimed responsibility for the attack on Twitter. The insurgents, who have been at war with the government for 15 years, often target local security forces.