An Afghan army soldier turned his weapon on U.S. servicemembers Saturday, killing three and injuring another in eastern Afghanistan.
The Afghan soldier was killed during the attack, said Attahullah Khogyani, spokesman for the provincial governor in Nangarhar province. Afghan officials initially said two servicemembers had been killed, but U.S. officials later said a third had died.
"On my way here I was informed that U.S. servicemembers were killed and wounded in an attack in Afghanistan," Vice President Mike Pence said during remarks at an event in Wisconsin on repealing Obamacare, according to ABC News.
"The president and I have been briefed; the details of this attack will be forthcoming. But suffice it to say, when heroes fall, Americans grieve. And our thoughts and prayers are with the families of these American heroes," he added.
The Taliban claimed responsibility for the shooting in a statement by spokesperson Zabiullah Mujahid, who said a person loyal to the terror group infiltrated the Afghan army “just to attack foreign forces.”
The attack occurred in Achin district, where U.S. special forces have been fighting alongside Afghan troops against Islamic State and Taliban militants, Khogyani said, according to Reuters.
Achin has been the scene of worsening violence in recent months as U.S. special forces and elite Afghan commandos intensify their efforts against ISIS loyalists in the region, a group known as ISIS Khorasan or ISIS-K, according to the Military Times.
Saturday's attack also comes as the Trump administration debates sending up to 5,000 additional American troops to Afghanistan to the help break what senior military leaders have declared a stalemate.
Such insider attacks have happened before in Afghanistan. In March, another Afghan soldier was killed after he opened fire on foreign forces at a base in Helmand province, wounding three U.S. soldiers.
Contributing: Associated Press