U.S. defense officials say that special operations forces launched a rescue mission to retrieve two men kidnapped by insurgents in Afghanistan last month. The hostages were not there when the rescue team arrived.

Pentagon press secretary Peter Cook says the rescue mission was approved by Defense Secretary Ash Carter and authorized by the president.

Officials say the mission was delayed one day because of questions about the intelligence and whether the hostages, an American and an Australian, were there.

The officials said that when U.S. commandos arrived at the location, they killed seven enemy fighters. They said that based on interviews with people at the site, it's still not clear if the hostages were ever there. The officials were not authorized to discuss the matter publicly, so spoke anonymously.