The lawsuit is filed on behalf of the families of three killed and 13 injured by a Saudi military trainee at a base in Florida.

Victims of a 2019 shooting at a military base in the US state of Florida and their families are suing Saudi Arabia, claiming the kingdom knew the gunman had been radicalised and that it could have prevented the killings.

The lawsuit was filed on Monday in the Northern District of Florida on behalf of the families of the three who were killed and 13 others who were injured, including sheriff’s deputies.

Mohammed Saeed Alshamrani, a Saudi Air Force officer training at the Naval Air Station Pensacola, shot and killed three US sailors on December 6, 2019.

The lawsuit comes nine months after US officials revealed that Alshamrani had communicated with al-Qaeda operatives about planning and tactics in the weeks leading up to the attack and that he had been radicalised before coming to the US for a military training programme.

The lawsuit alleges that Saudi Arabia knew of Alshamrani’s associations with al-Qaeda and his radicalisation and yet failed to monitor, supervise or report him.

The suit also claims that other Saudi trainees at the base knew in advance about plans for the shooting but did nothing to stop it.

It says the gunman told fellow Saudi trainees at a dinner party the night before the attack that he planned to carry out the shooting the following day, but instead of reporting it, they called in sick in the morning. One recorded the shootings while standing outside the building; two others watched from a car nearby.

“None of the Royal Saudi Air Force trainees at the scene of the attack reported Al-Shamrani’s behaviour nor did they try to stop” it, the lawsuit says. “Because they supported it.”

The complaint also says Alshamrani’s fellow Saudi trainees were aware that he had purchased and stored firearms and ammunition in his barracks, and that he had posted and shared extremist material on social media and screened videos of mass shootings before the attack.

‘Trojan Horse’

“Al-Shamrani was a Trojan Horse sent by his country, the Kingdom of Saudi Arabia, and its proxy, al-Qaeda in the Arabian Peninsula, for flight training at Naval Air Station Pensacola, Florida, under the auspices of a programme tied to billions of dollars in military arms sales from the United States to the Kingdom,” the lawsuit states.

“Little did the American people know that such an arrangement would soon devolve into a horrific, Faustian bargain.”

One month after the shooting, then-Attorney General William Barr announced that 21 Saudi trainees found to have had pro-armed group or anti-American sentiments on social media pages or “contact with child pornography” were being sent home.

The complaint seeks monetary damages against Saudi Arabia under an exemption of the law that allows for lawsuits against foreign countries arising from acts of “terrorism”.

Though then-President Donald Trump told reporters that he had spoken with Saudi Arabia’s king and that the kingdom would help the victims’ families “very greatly,” the kingdom breached the agreement by failing to compensate or engage with them, according to the lawsuit.

A spokesperson for the Saudi embassy in Washington did not immediately return an email seeking comment Monday.

The suit comes as the Biden administration has signalled a tougher stance on Saudi Arabia after a mostly cosy relationship for the last four years between Trump and Crown Prince Mohammed bin Salman.

Earlier this month, President Joe Biden made good on a campaign commitment to end US support for a six-year Saudi-led bombing campaign in Yemen. He made clear, however, that the US would not completely abandon military assistance for the kingdom.