At least 20 police officers were killed in clashes with Taliban Friday night in Afghanistan’s Helmand province, police officials said Saturday. The insurgents attacked several checkpoints in the Musa Qala district, a Taliban stronghold, in the encounter that reportedly lasted for hours.

At least 10 police officers were injured, Mohammad Ismail Hotak, the head of the province's joint coordination of police and military operations, told the Associated Press (AP). According to Brigadier Abdul Wadood, a senior army officer in the province, 40 insurgents were killed in the attack, Xinhua reported.

"The clashes continued for several hours. Nobody came for our help. The fighting continued until all our personnel were either left dead or wounded," a security source told Pajhwok Afghan News, an online news agency.

The militants reportedly set three police vehicles on fire and took over two other vehicles, which had weapons and armory.

In a bid to overthrow the U.S.-backed government and impose Islamist rule, Taliban has targeted Afghan government positions this year and plans to take over territories in remote areas of the country, Reuters reported.

Last month, at least 19 police officers were killed in a Talibani attack in Helmand's Naw Zad district.

Following the withdrawal of the United States and NATO forces from Afghanistan, security officials in the country are fighting alone against the insurgents this year. Between Jan. 1 and May 7, the clashes claimed the lives of around 2,322 army, police and local police personnel, 53 percent more than those killed during the same period in 2014, according to NATO, the AP reported.