The co-pilot accused of attacking the captain of an Israel-bound flight with an axe and attempting to seize control of the aircraft was an Omani national who had previously been barred from flying by his home country's airline over concerns about extremist views, officials said Saturday.

The co-pilot has been identified as Hamam al-Hammami, according to three people with knowledge of the situation, including a Gulf and a Western diplomat, who spoke on condition of anonymity because they were not authorized to brief the media.

The United Arab Emirates, which is leading the investigation, has described the episode as a “terrorist attack.” It said the co-pilot struck the captain with the cockpit's crash axe on Wednesday and tried to take control of the plummeting plane. His actions nearly brought down the flight, which was carrying 182 people, before passengers and others rushed in and subdued him.

The new details have raised questions about how thoroughly FlyDubai vets prospective employees — and how a co-pilot came to be on a flight filled with Israeli passengers despite Israel's strict security protocols. Israel has said it maintains agreements with foreign carriers to keep pilots from nations without diplomatic ties from flying there. Israel and Oman have no formal diplomatic relations. The UAE government has earned a reputation for effective measures against extremist activity, but it has bristled in the past over criticism of security lapses.

The incident occurred at a sensitive time for Israel, one week before the anniversary of the Hamas-led attack of Oct. 7, 2023, which sparked the war in Gaza. It also came weeks before a highly contentious election in which security — and the Oct. 7 security failures — have been central issues.

Separately, a regional official and a person familiar with the matter said the co-pilot had been barred from flying by Oman over concerns that he had adopted extremist views. The official said he was moved to an administrative job at Oman Air. Both spoke on condition of anonymity to discuss the ongoing investigation, and they gave no details about the alleged extremist views.

The co-pilot was later hired by UAE-based FlyDubai, according to the person familiar with the matter. It was not immediately clear to what extent he was vetted. The Gulf diplomat said he underwent standard security checks before being hired, but the checks appear to have focused on whether he had been convicted of criminal charges rather than probing more deeply into his background for potential signs of radicalization.

The regional official said security agencies from four regional countries are working to establish the co-pilot's motives, aided by the United States and other Western governments. The Gulf diplomat said investigators are seeking to determine whether he acted alone or “has any connection with any extremist groups.”

The official said the co-pilot was born in the UAE and that his mother is Syrian. He obtained Omani nationality through his father, who is also an Omani national. The co-pilot had also traveled to Syria, the official said, without providing details.

Israeli Prime Minister Benjamin Netanyahu said on Friday that the co-pilot had undergone “Islamist radicalization,” but he provided no evidence. There was no immediate comment from Israel's government on Saturday.

A FlyDubai spokesperson said in an email that the airline could not comment beyond its official statements and acknowledged “there are many questions at this stage.” Oman Air did not respond immediately, and Oman's government has said nothing publicly in response to repeated questions since the incident. Until they do, the questions at the heart of the case — why Oman barred him from flying, and how he came to be hired by FlyDubai — remain unanswered as the multinational investigation continues.

In a statement to The Associated Press, Royal Air Maroc, Morocco's national carrier, said the co-pilot “completed a three-month theoretical training period with the airline in 2025, as part of the pre-employment process. At the end of this training period, his application was not selected for employment.” No further details were provided.

Keith Coles, a spokesperson for Buckinghamshire New University in England, told the AP that al-Hammami had previously completed a distance-learning course in aviation management at the university but “did undertake any pilot training.” The timing was not disclosed.

Little else was immediately known about the co-pilot's background. His Instagram account was active until the day of the flight and was then deleted.

Crash axes are standard equipment that airlines are generally required to carry in the cockpit, intended for use in emergencies to break open a window to escape or a panel to access a fire. Cockpit doors on commercial airliners are normally kept locked in flight under security procedures widely adopted after the Sept. 11, 2001, attacks, and can typically be opened only from inside.

The captain, who was badly wounded, has said he used his remaining energy while under attack to unlock the cockpit door, allowing people who had noticed alarming sounds to come in, tackle the co-pilot and stabilize the flight as passengers screamed.

The plane made an emergency landing in Saudi Arabia after a descent so extreme that part of the rudder was torn away, and aviation experts have marveled that it did not crash. FlyDubai has said crew members traveling on the plane helped to stabilize it and land it. They have not been publicly identified.

Both the captain and the co-pilot were later taken to the UAE. The passengers, most of them Israeli, flew home on a separate plane later on Wednesday, to cheers.

This story was originally featured on Fortune.com.