In a statement on Wednesday, the Pentagon said the decision was made per new guidelines from the Centers for Disease Control and Prevention (CDC), reports Xinhua news agency.
The terrorist attack was carried out by ISIS gunman, General Kenneth Franklin McKenzie, Commander of the United States Central Command, told reporters at a Pentagon news conference on Thursday
The Pentagon's massive task of removing service members and equipment out of Afghanistan is nearly complete and the US military mission is slated to end by August 31.
“It's an honour and a privilege to serve as our country's 28th Secretary of Defense, and I'm especially proud to be the first African American to hold the position. Let's get to work,” Austin tweeted.