Kabul: At least 20 Taliban militants, including four commanders, have been killed in Afghanistan's Helmand province, a news agency reported on Tuesday.

Afghan forces backed by NATO troops launched an operation in Washir district, around 550 km from Kabul, over the past three days.

The four commanders have been identified as Mullah Ahsan, Mullah Abdullah, Mullah Abdul Haq and Mullah Assadullah, provincial spokesman Daud Ahmadi said on Tuesday.

Meanwhile, Taliban spokesman Qari Yusuf Ahmadi confirmed the clash in Washir district but said only three Taliban men were killed.

Helmand is the hotbed of Taliban militants and notorious for poppy cultivation.