KABUL, Oct. 21 (Xinhua) -- At least 15 army cadets were killed and four others wounded as suicide blast happened in Kabul, capital of Afghanistan on Saturday afternoon, the defense ministry confirmed.

"A suicide bomber detonated his explosives close to the Marshal Fahim military university in western part of Kabul, killing 15 army cadets and injuring four others," Dawlat Waziri, spokesman for the ministry of defense, said in a statement.

No group has claimed responsibility for the attack so far.

This week has been a brutal one for Afghanistan. Suicide bombers on Friday detonated their explosives among the prayers on two Shia mosques in the country, one in Kabul and another in western province of Ghor, killing 56 people and wounding 55 others.