WASHINGTON — American commandos captured a suspect in the 2012 attacks in Benghazi, Libya, American officials said on Monday, bringing into custody a second man accused in the terrorist attacks that have been used by Republicans as a political spear against the Obama administration.
The man, Mustafa al-Imam, was caught on Sunday in the area of Misurata, Libya, brought aboard an America warship and will be taken to the United States to face criminal charges, the officials said. Four Americans, including Ambassador J. Christopher Stevens, were killed in bloody assaults at a diplomatic compound and a C.I.A. base a mile away that came under heavy fire. More than a dozen people have been charged, and one is standing trial.
“To the families of these fallen heroes: I want you to know that your loved ones are not forgotten, and they will never be forgotten,” President Trump said in a statement on Monday. “Our memory is deep and our reach is long, and we will not rest in our efforts to find and bring the perpetrators of the heinous attacks in Benghazi to justice.”
The team of commandos — members of the Navy SEAL Team 6 and the F.B.I.’s Hostage Rescue Team — surprised Mr. Imam, the officials said. One said he was unable to resist. Details about the operation were limited, but the officials said that plans to apprehend him had been in the works for months as the American military waited for authorization from the White House.
Officials said he was living in Tripoli and had recently traveled to Misurata, a coastal city between Tripoli and Benghazi. The military’s Joint Special Operations Command had been watching Mr. Imam closely along with others thought to have participated in the attacks.
The arrest of the man shows that President Trump, who vowed during his campaign to fill the wartime prison at Guantánamo Bay with “bad dudes,” is willing to use civilian courts to prosecute terrorism suspects captured overseas. The capture also marks a victory for F.B.I. officials, who had feared that such prosecutions would stagnate under Mr. Trump and Attorney General Jeff Sessions.
Mr. Sessions has said for years that terrorism suspects should be held and prosecuted at Guantánamo Bay. Mr. Sessions has said that terrorists do not deserve the same legal rights as common criminals and that such trials were too dangerous to hold in the United States.
Earlier this year, the United States extradited a man suspected of belonging to Al Qaeda from Spain to stand trial in the United States. European allies refuse to release suspects to be sent to the prison at Guantánamo Bay, complicating Mr. Trump’s rhetoric about filling the prison but demonstrating the realities of fighting terrorism in 2017.
The F.B.I.’s Hostage Rescue Team has worked closely for years with the military’s elite units to make such arrests. In 2013, the F.B.I. team took part in an operation to arrest Ahmed Abu Khattala, who was charged in the Benghazi attack and is being tried in Federal District Court in Washington. If convicted, Mr. Khattala faces a potential sentence of life in prison.
It was not clear how the arrest of a second suspect could affect Mr. Khattala’s trial. But officials said Mr. Imam was one of the men filmed entering and leaving the diplomatic compound the night of the attack and was an associate of Mr. Khattala.
To capture Mr. Khattala, an F.B.I. agent and several Delta Force operators snatched him from a beachside villa on Libya’s coast, and Navy SEALs took him to a waiting warship, where he was interrogated. In another operation, SEALs and the F.B.I. captured an Al Qaeda suspect in 2013 as he returned home from morning prayers. He was taken to an American warship and had to be quickly flown back to the United States because of serious health problems. He later died of liver cancer before he could stand trial.