Unknown armed men shot and killed a senior police officer in Lashkar Gah, the provincial capital of Helmand province 555 km south of capital city of Kabul, a spokesman for provincial government said on Sunday.

"The police officer named Abdul Haleem who serves as police commander of Afghan Local Police Force (ALP) in Helmand's Marjah district, was attacked by two suspected militants at around 05:00 p.m. local time on Saturday in Kariz area of provincial capital Lashkar Gah," Daud Ahmadi told Xinhua.

The attackers fled by their motorbike, he said, adding an investigation was initiated by police in to the case.

No group has claimed responsibility for the incident so far, however, Taliban insurgents have in the past been blamed for attacking government security forces and tribal elders.

Taliban insurgents, whose regime was toppled in a U.S.-led incursion in late 2001, have intensified activities since the militant group announced to launch spring offensive against Afghan security forces and NATO-led troops stationed in Afghanistan on May 1.

Afghan security forces took full control of Lashkar Gah from NATO-led forces on July this year. At least four people have been assassinated in Helmand province over the past one month.

In separate incident, unknown armed men shot and killed Hazrat Mir police chief of anti-terrorism department of Darqad district of northern Takhar province on the same day Saturday.