WASHINGTON • A Libyan man accused of masterminding the 2012 Benghazi attack that killed a US ambassador and three others has been acquitted of murder but convicted on lesser terrorism charges.
After a seven-week trial in a civilian court in Washington, a jury on Tuesday cleared Ahmed Abu Khattala - the first person tried over the fiery raid on the US complex in the Libyan coastal city - of the most serious of the charges he faced.
Prosecutors were apparently unable to prove to the jury that Khattala, leader of a militant group who had been photographed watching the attack on Sept 11, 2012, was directly to blame for the deaths of US Ambassador Christopher Stevens, a second State Department official, and two Central Intelligence Agency (CIA) contractor guards at the consulate and a CIA annex.
He was convicted of only four of 18 charges he faced - supporting terrorists, conspiracy to provide support to terrorists, carrying a semi-automatic weapon during a violent crime, and damaging US property.
That was far weaker than the picture prosecutors had presented of Khattala as the person who plotted and directed the deadly assault.
His trial was seen as a test case for foreign terror suspects forcibly brought to the US and placed before civilian courts.
Federal Bureau of Investigation (FBI) counter-terrorism division assistant director Grant Mendenhall said in a statement: "This investigation demonstrates the FBI's ability to investigate terrorist attacks against Americans even in the most difficult conditions, determine who perpetrated the acts and bring those actors to justice."
The 2012 attack, undertaken on the 11th anniversary of the 9/11 attacks, was carried out by some 20 men armed with grenades and heavy weapons.
Mr Stevens and the second State Department official, Mr Sean Smith, died of smoke inhalation after the consulate caught fire, while the two CIA contractors, Mr Glen Doherty and Mr Tyrone Woods, were killed in the firefight by mortar rounds.
US prosecutors said Khattala was at the scene in regular contact with the attackers via cellphone before, during and after the assault.
The death of Mr Stevens stunned Americans and became the focus of a politically-charged investigation by congressional Republicans of then secretary of state Hillary Clinton, who was accused of not protecting the diplomats.
Khattala was captured in 2014 in a raid by US special forces, who then placed him aboard a navy ship where he was interrogated for a week before being delivered to the United States.
The raid and the legal case were based in part on a Libyan informant, an associate of Khattala, who was eventually paid a US$7 million reward and granted asylum in the US.
Khattala faces a total of 50 years in prison for the terror and destruction offences, and up to life in prison for the weapons charge. No date for sentencing was set.
There was no immediate reaction from the White House.
CIA director Mike Pompeo released a statement saying: "Today, a small measure of justice was meted out."