The Taliban staged a complex attack that killed at least 10 Afghan soldiers in the southern province of Helmand, an Afghan official said Saturday.

A powerful explosion first hit an army checkpoint late Friday, followed by a protracted gunbattle lasting a number of hours, Omar Zwak, a spokesman for the provincial governor, told the Associated Press. The attack also wounded four soldiers, he said.

The Taliban dug a tunnel into the base in volatile Sangin district and then blew it up before their fighters could attack the compound, Nawab Zadran a spokesman for 215 Maiwand Army Corps in southern Afghanistan told AFP.

"There were 18 soldiers in the base at the time of the attack providing security for the people of Sangin. Four soldiers were wounded and four repelled the Taliban attack bravely," Zadran said.

Taliban spokesman Qari Yusouf Ahmadi announced the militant group's responsibility, adding that insurgents had also seized weapons and ammunition. The insurgents have a strong presence in Helmand province, especially in the Sangin district in which the attack took place.

The Taliban have increased their attacks against Afghan army bases and checkpoints in numerous provinces over the last few days.

A similar attack killed six Afghan soldiers on Thursday, when a suicide bomber detonated a car laden with explosives outside an army compound in the northern province of Balkh. Militants then stormed the compound. The Taliban quickly claimed responsibility for the attack.

On Tuesday, another attack on a checkpoint in Balkh province killed at least seven Afghan soldiers. At the time, the Taliban said they also captured four Afghan troops and seized weapons and ammunition.

On Monday, an American soldier was killed in combat in northern Kunduz province. The Taliban claimed they were behind a fatal roadside bombing that targeted American and Afghan forces in Kunduz.

Also on Saturday, eight prisoners escaped from a Taliban-controlled jail in Afghanistan's south-eastern province of Ghazni, a statement by the Afghan Ministry of Defense said.

The escapees were members of Afghanistan's security forces being detained at the prison in the province's Qarabagh district, the statement reads. It is not yet clear how long they had been imprisoned for.

After the prison break, they reached an area controlled by an army base, the Ministry of Defense said.

Afghan special forces have freed hundreds of their companions from Taliban-run prisons over the last few years.

In another escape some eight years ago, nearly 500 members of the Taliban fled a fortified Afghan prison in southern Kandahar province by digging a tunnel hundreds of meters in length right beneath the prison.

Afghan president Ghani freed more than 900 Taliban prisoners this summer, in a show of good faith.

The Taliban now control or hold sway over practically half of Afghanistan. The insurgents continue to stage near-daily attacks targeting Afghan and U.S. forces, as well as government officials, even as they hold peace talks with a U.S. envoy tasked with negotiating an end to the 18-year conflict, America's longest war. Scores of Afghan civilians have been killed in the crossfire which has raged and due to roadside bombs planted by militants.

Winter once marked a slowdown in what is known as the "fighting season," with Taliban fighters returning to their villages while snow and ice made attacks more difficult to pull off. But in recent years, the distinction between seasons has all but vanished.