An ambulance arrives at the scene of a blast in Kabul, capital of Afghanistan, Sept. 17, 2019. An explosion rocked Police District 9 in the Afghan capital of Kabul on Tuesday as the country is to hold a presidential election next week, police spokesman Ferdaus Faramarz said. (Xinhua/Rahmatullah Alizadah)

KABUL, Sept. 17 (Xinhua) -- An explosion rocked Police District 9 in the Afghan capital of Kabul on Tuesday as the country is to hold a presidential election next week, police spokesman Ferdaus Faramarz said.