FlyDubai co-pilot was reportedly flagged before attack. So how was he cleared to fly?

This morning, the investigation into that attempted attack on a fly Dubai flight is now

focusing on a big question. How was the co-pilot allowed to fly in the first place? Investigators

say the co-pilot attacked Captain Smith Machar with an emergency crash axe, then tried to take

control of the plane as it flew from Dubai to Tel Aviv. That axe wasn't smuggled on board. It

was already in the cockpit, standard emergency equipment used on passenger planes. The plane

started dropping fast. Machar was badly injured, but managed to open the cockpit door, allowing

passengers and crew to get inside and restrain the co-pilot. Reserve pilots on board took the

controls and landed the plane in Saudi Arabia. Investigators now believe the co-pilot likely

acted alone. U.S. officials say there's currently no indication Iran directed the attack, though

the investigation is still early. But there are new questions about his background. Sources tell

CNN he was removed from Oman's national airline last year after concerns about extremist views

And yet he later went to work for Fly Dubai and was cleared to fly an Israel-bound passenger jet

Aviation experts say there is no single international standard for pilot background

checks and information about employment or security concerns doesn't automatically follow a pilot from one airline or country to another. Mochar is recovering in Abu Dhabi where Dubai's

crown prince has now visited him on Sunday. The UAE is leading the investigation. Israel

and Saudi Arabia are also investigating