More than 100 members of Afghanistan's security forces were killed on Monday when Taliban militants detonated a car bomb outside a military base before storming the building and initiating a firefight with Afghan forces.
All of the Taliban militants were killed in the gunfight, which was launched after an armoured vehicle packed with explosives rammed the military base, officials told Reuters.
"We have information that 126 people have been killed in the explosion inside the military training centre," the senior defence ministry official said on condition of anonymity. A provincial official also said more than 100 people were killed.
More than 40 members of the country's elite intelligence forces were killed in the attack, which officials said made it one of the worst attacks on the intelligence service in the 17-year war.
The attack took place in Maidan Shahr, the capital of the Maidan Wardak province, 50 kilometres southwest of Kabul.
After the militants set off the bomb, between two and three gunmen entered the sprawling base, an Afghan official said.
Pictures from the scene showed the corner of a square building partially collapsed and surrounded by a blanket of snow.
Armed security were patrolling the area while an Afghanistan military helicopter flew above the scene of the attack.
The gunmen who tried to enter the compound were shot dead, Mohebullah Sharifzai, spokesman for the Maidan Wardak provincial governor confirmed.
"A [second] car, packed with explosives, was also discovered and defused," he said.
The province's health director earlier said he expected the number of casualties to rise and that all of the victims had not been found.
The government had earlier said 12 people were killed and more than 28 security officials injured in the attack.
Taliban militants are active in the province and carry out regular attacks against security buildings and government institutions. The group's spokesman, Zabihullah Mujahid, claimed responsibility for the attack.
Some of the wounded were taken to provincial hospitals, while more serious cases were transferred to Kabul, Salem Asgherkhail, head of the area’s health department, said.
Meanwhile, the Taliban said they were holding fresh discussions with US special envoy Zalmay Khalilzad in Qatar, just days after threatening to pull out of peace talks with the American government and reiterating its refusal to speak with the internationally recognised Afghan government.
"Talks between Taliban leaders and US officials have started today in Qatar," Taliban spokesman Zabiullah Mujahid said in a statement.
Efforts to negotiate a peace deal to end the 17-year war in Afghanistan have been beset by disagreement in recent weeks, with the United States opposing the Taliban's decision to shut the Afghan government out of discussions.
Taliban attacks have increased in recent weeks amid a period of renewed peace talks and coming presidential elections.
The United States is holding peace talks with the Taliban in an attempted to end the war that has cost them more than a trillion dollars and both sides thousands of lives.
On Monday, the Taliban met with US special envoy Zalmay Khalilzad in Qatar, where the group have an embassy.
The Taliban refuse to hold direct talks with the Afghanistan government, instead speaking only to the United States who they view as the puppet master behind the country's internationally supported administration.
The two sides are struggling to agree on an agreement to end the 17-year warm, which began in the wake of the 9/11 terror attacks. The Taliban want a significant prisoner swap, while the US wants the two Afghan sides to meet face to face.
Meanwhile, the Afghanistan government is facing a presidential election in June, a race that started in earnest on Sunday with the deadline to announce candidacy.
The race is set to be a rerun of the disputed 2014 election in which Abdullah Abdullah refused to accept the victory of his rival Ashraf Ghani, leading to a power-sharing arrangement brokered by the international community.