Four American service members were killed in a mortar attack on Bagram Airfield in Afghanistan on Tuesday, a senior defense official confirmed to NBC News.
The four International Security Assistance Force service members died after an indirect fire attack in eastern Afghanistan, the ISAF said in a statement.
The attack came just hours after the White House announced that the U.S. will soon meet with Taliban representatives for the first time to negotiate a peaceful settlement to end the war in Afghanistan.
U.S. officials said the negotiating conditions will require the Taliban to cut all ties to al Qaeda, end the violence and accept the Afghan constitution.
The negotiations will take place in Doha, Qatar, where the Taliban opened an office for the purpose of negotiating directly with the Afghan government.
The attack also came on the same day international forces handed over control for security of the entire country to Afghan security forces, the milestone the United States and its allies had been working towards during the almost 12-year conflict.