WASHINGTON 

An American and an Italian hostage were killed along with two Americans working with al-Qaeda in U.S. counterterror operations earlier this year, the White House said Thursday.

Warren Weinstein, a U.S. citizen held by al-Qaeda since 2011, and Giovanni Lo Porto, an Italian national held by the terror group since 2012, were killed in January. The operation targeted one of the group’s compounds in the border region between Afghanistan and Pakistan.

President Barack Obama said in nationally televised remarks that he takes full responsibility for the deaths of the two men, and “I profoundly regret what happened.”

"I realize that there are no words that can ever equal their loss," he said of the families of the deceased. 

“Based on the intelligence that we had obtained at the time, including hundreds of hours of surveillance, we believed that this was an al-Qaeda compound, that no civilians were present and that capturing these terrorists was not possible,” Obama said. “And we do believe that the operation did take out dangerous members of al-Qaeda.”

Ahmed Farouq, an American who the White House says was an al-Qaeda leader, was killed in the same operation.

Obama defended the legality of the strike, saying that it fell under the guidelines for U.S. operations in the region.

The White House also concluded that Adam Gadahn, an American al-Qaeda spokesman, was killed in a separate operation in January.

The U.S. did not specifically target Farouq or Gadahn, and “did not have information indicating their presence at the sites,” according to the White House.

Obama did not comment on their deaths during his remarks, instead focusing on Weinstein and Lo Porto, and did not take questions from reporters before exiting the White House briefing room.