KABUL: A powerful explosion rocked the Afghan capital early Monday, rattling windows and sending smoke billowing from Kabul's downtown area near the US Embassy.

At least 15 people have been wounded, said ambulance worker Ahmad Zahir.

The explosion occurred as the streets in the capital were packed with morning commuters. Officials and police were at the scene of the blast and few details were available. Ambulance sirens screamed throughout the downtown area as they rushed to the scene.

Kabul's chief police spokesman, Firdous Faramaz, could only confirm the explosion, but was unclear on the target or the type of explosive device.

The capital has been relatively quiet in recent months following a spate of violent explosions, many claimed by the Islamic State affiliate that operates in Afghanistan. Both the Taliban and the Islamic State operate in Kabul.

The attack comes as the Taliban and the United States hold talks in the Middle Eastern state of Qatar, where the militant group maintains a political office.