Two US soldiers confirmed dead as suicide bomber rams vehicle filled with explosives into convoy of foreign forces.
The Taliban launched a major attack on an army base in southern Kandahar province, killing at least 43 Afghan soldiers.
The brazen assault on Thursday began with two suicide car bombings, setting off several hours of fighting.
Of 60 soldiers manning the base, 43 were killed, nine wounded, and six missing after Taliban fighters stormed the camp in the middle of the night, the defence ministry said in a statement.
At least nine Taliban were also reported killed at the base in the Chashmo area of Maiwand district.
It was the third assault on a security installation this week. Eighty people were killed and 300 wounded in attacks on Tuesday in Afghanistan‘s southeast – the bloodiest day in the war-torn country in almost five months.
The Taliban claimed responsibility for Thursday’s attack. Taliban spokesman Qari Yousuf Ahmadi said at least 60 Afghan soldiers were killed and wounded many others, he said.
Defence ministry spokesman Dawlat Waziri told AFP news agency the assailants detonated at least one explosive-packed truck and razed the compound.
“We think the militants used an explosive-packed Humvee vehicle to detonate the gate of the base and we are looking to see if there was more than one,” Waziri said.
“Unfortunately there is nothing left inside the camp. They have burned down everything they found inside. We have sent a delegation to assess the situation. The base is under ANA [Afghan National Army] control,” he added.
The US launched an air strike in response to the attack, a spokesman at the coalition military command in Kabul said.
Afghan forces have struggled to combat a resurgent Taliban since the US and NATO forces formally concluded their combat mission at the end of 2014.