It is too early to say why a pilot stabbed another pilot and tried to take over a flight from Dubai to Tel Aviv, Israel's prime minister has said.
The Flydubai plane plunged more than 17,000ft (5,200m) two hours into its journey on Wednesday during the incident, before passengers and crew overpowered the attacker and retook control to land safely.
The stabbed pilot, Indian national Captain Smit Machchhar, is now in hospital in a stable condition, and has been hailed a "true hero" by Prime Minister Benjamin Netanyahu.
One passenger, Yaniv Hayun, described how he put the attacker, who was trying to disable the plane, in a chokehold before other passengers helped pin him down.
The alleged attacker was arrested in Saudi Arabia but is expected to be transferred to the United Arab Emirates, where the plane took off from, Netanyahu told Fox News.
Asked whether there was any indication of Iran's involvement, he replied: "It's too early to say".
US President Donald Trump said he had spoken with Netanyahu following the incident, saying it seemed as though the attacker was "perhaps a terrorist" or there were other reasons behind the attack.
Israeli Defence Minister Israel Katz has also called it an "attempted jihadist terror attack", without giving any details.
Netanyahu told CNN Israel did not have any warning or advance intelligence about the incident on the plane, which was flying 174 people to Israel.
Flydubai's flight FZ1073 took off from Dubai International Airport in the UAE at 03:05 GMT (07:05 local time), en route to Ben-Gurion Airport.
Two hours later, the 17,000ft drop in altitude was reported on the plane tracking website Flightradar24 and minutes later the plane signalled an emergency code - squawk 7700 - before switching it to a squawk 7500 code reporting a hijacking.
Around 20 minutes after these codes were signalled, the plane started its manual descent for landing into Saudi Arabia. Less than an hour later, the plane returned to squawk 7700.
Eyewitness accounts and a statement by Netanyahu confirmed one of the pilots had stabbed the other and, according to the Israeli prime minister, "apparently tried to crash" the aircraft.
One passenger, Hayun, described how he and others on the flight had restrained the attacker.
"The pilot who was stabbed was simply very close to the door, so it was hard for us to open it," Hayun said in a video posted on social media by the prime minister's office, but before the stabbed pilot collapsed, he was able to open the door.
Yaniv said he put the attacker, who was trying to disable the plane, in a chokehold before other passengers helped pin him down.
He added that he "pulled the controls" of the plane and after it levelled out, another pilot took over control.
Airline Flydubai confirmed two on-duty crew travelling on the flight landed the plane.
Zvika Meness, another passenger, told Israeli public broadcaster Kan News that he and other passengers tied the attacker up "with his own zip ties and with the multimedia headphones".
He said: "There are children and families here who have been through a very severe, highly traumatic event."
