Taliban militants wearing Afghan army uniforms killed at least 50 soldiers in a gun and suicide attack at a base in northern Afghanistan, the US military said, as the extremists ramp up their campaign against beleaguered government forces.

Two of the attackers blew themselves up and seven were killed in the assault near Mazar-i-Sharif city on Friday which lasted several hours and targeted soldiers at a mosque and dining facility, the Afghan defence ministry said.

One of the assailants was detained.

A US military spokesman said "more than 50" Afghan soldiers were killed in the attack claimed by the Taliban, while Afghan officials put the death toll at eight with 11 wounded.

General John Nicholson, the top US commander in Afghanistan, praised Afghan commandos for bringing the "atrocity to an end".

The latest deadly attack against an Afghan military site underscores rising insecurity in the war-torn country as it braces for an intense fighting season in the spring.

Afghan security forces, beset by killings, desertions and non-existent "ghost soldiers" on the payroll, have been struggling to beat back insurgents since US-led NATO troops ended their combat mission in December 2014.

According to US watchdog SIGAR, casualties among Afghan security forces soared by 35 percent in 2016, with 6,800 soldiers and police killed.

Nicholson in February told the US Senate Armed Services Committee in Washington that he needed "a few thousand" more troops to help train and assist the Afghan forces.

The US has around 8,400 troops in the country with about another 5,000 from NATO allies assisting a much larger Afghan force in the war against the Taliban and other Islamist militants.

- Military sites targeted -

Several military helicopters hovered over the base during Friday's attack and ambulances later took away the bodies of the victims, an AFP correspondent said.

The facility in Balkh province is home to the Afghan army's 209th Corps.

The last major attack against a military site was in early March when gunmen disguised as doctors stormed the Sardar Daud Khan hospital -- the country's largest military hospital -- in Kabul, killing dozens.

Afghan officials put the death toll at 50, but security sources and survivors told AFP more than 100 were killed in the brazen and savage attack.

The Islamic State group claimed it was behind the operation -- hours after the more powerful Taliban denied responsibility for the raid.

That assault came a week after 16 people were killed in simultaneous Taliban suicide assaults on two security compounds in the capital.

More than a third of Afghanistan is outside government control and many regions are fiercely contested by various insurgent groups, as Kabul's repeated bids to launch peace negotiations with the Taliban have failed.

Earlier this month the US military dropped its largest non-nuclear bomb on Islamic State group hideouts in eastern Afghanistan, killing nearly a hundred militants.

The attack triggered global shockwaves, with some condemning the use of Afghanistan as what they called a testing ground for the weapon, and against a militant group that is not considered as big a threat as the resurgent Taliban.

Source: AFP