JALALABAD, Afghanistan, Dec. 7 (Xinhua) -- At least 20 militants of Islamic State (IS) were killed in Afghanistan's eastern province of Nangarhar overnight as security forces continued in mopping-up operations, authorities said Friday.

In one incident, 17 IS militants including two divisional commanders of the outfit were killed after the National Directorate of Security (NDS), the country's primary intelligence agency, attacked IS hideouts in Haska Mina district, the provincial government said in a statement.

Six militants' defense positions and hideouts together with amount of weapons and ammunition were also destroyed by the security forces, the statement added.

In neighboring Pachir Aw Agam district, three IS fighters were killed after Afghan Air Force launched an airstrike in the mountainous district, according to the Afghan Ministry of Defense.

The mountainous province, 120 km east of Kabul, has been the scene of clashes between security forces and IS militants from time to time.

Clashes have forced thousands of villagers to flee to safer places.

The IS group has yet to make comments on the report.