They said the cabin crew entered the cockpit and took control of FlyDubai flight FZ1073 from the United Arab Emirates to Israel, which diverted to Saudi Arabia as it flew over Jordanian airspace.
One of the officials identified the attacker as an Omani national.
An Israeli official had earlier told Reuters the plane transmitted emergency signals on Wednesday after the pilots got into a physical altercation with each other.
The aircraft's data appeared to show that it had suddenly and rapidly descended by about 4200 metres in less than 30 seconds before a first emergency signal was sent, according to flight-tracking website Flightradar24.
About the time the plane landed in Saudi Arabia, Doron Spielman, a spokesperson for the Israeli prime minister's office, told Reuters the incident was not believed to have been a hijacking, describing it as a "different incident".
The Israeli officials, speaking on the condition of anonymity to brief reporters, said Israel's assessment was that the incident was an attempted "terror attack" and not related to any kind of mental health issue with either of the pilots.
In a video purportedly of an Israeli passenger on board the FlyDubai flight and carried widely by Israeli media, the passenger said one of pilots was seriously injured and the other was slightly injured, after one of the pilots was stabbed.
Saudi Arabia's Tabuk airport, where the plane landed, said that both pilots had been hospitalised after suffering injuries.
Neither the airport nor the purported Israeli passenger identified the attacker.
The Boeing 737 plane, which Israeli media said had about 150 Israeli passengers on board, transmitted three emergency signals before landing at Tabuk airport in northwestern Saudi Arabia, according to Flightradar24.
The incident heightened security fears in Israel weeks before Israelis vote in the first election since the Hamas-led October 7, 2023 attacks, with Israel's security figuring prominently in the campaigning.
Responding to the incident on X, far-right security minister Itamar Ben-Gvir wrote "terrorism is a devil with whom no agreement must be reached".
Israeli media published conflicting reports on the incident, with some outlets reporting that a pilot had tried to crash the passenger plane in an alleged suicide attempt.
Some Israeli media outlets identified the pilots as Omani and Emirati nationals, while others said they were Russian and Ukrainian.
The incident triggered national security consultations in Israel, which has no official diplomatic relations with Saudi Arabia, where the plane landed.
In an earlier statement, the Israeli prime minister's office said the situation was "under control" and all measures were being taken to bring the Israeli passengers back to Israel.
Benjamin Netanyahu had cleared his schedule for the rest of the day to manage the crisis, an Israeli official said.
Netanyahu on Sunday met UAE President Sheikh Mohamed bin Zayed Al Nahyan during a a rare visit to the Gulf country.
Israel and the UAE have forged close security, military and economic ties since establishing diplomatic ties in 2020.
The UAE has yet to comment on the incident, while the Dubai-owned airline has only said that the flight experienced an "incident" and diverted to Tabuk, where it landed safely, and that all passengers were safe and accounted for.
Yasmin Abukasis said her daughter Miriam, who was among the passengers on the flight, had told her that she had heard screaming and that a man holding a knife had forced one of the pilots onto the floor, and that there was blood everywhere.
Israeli media published a photo purportedly taken from inside the plane, which appeared to show a passenger's blood-soaked shirt.
Flydubai operates daily return flights between Dubai and Tel Aviv, a route that is popular among Israeli nationals.
