A bomb threat that turned out to be a hoax, made by a "joking" Polish passenger, forced an airliner flying from Warsaw to Egypt to make an emergency landing in Bulgaria today.

Bulgaria’s Prime Minister Boyko Borisov said it was a “completely false” alarm caused by a "drunken Pole talking rubbish".

The Airbus A320 of Polish Small Planet Airlines landed just before dawn in the Black Sea city of Burgas, where authorities said all 161 passengers and crew were evacuated safely.

"There is no explosive device on board the plane that made an emergency landing," the interior ministry said in a statement after conducting a second check of the plane.

Prosecutors said a 67-year-old Pole had alerted crew about a possible bomb on board. He has been arrested and could face up to 15 years in jail.

Earlier today, the Polish airline said in a statement that the man had "informed the cabin crew about the explosive he might be carrying. He later admitted it was a joke."

A police spokeswoman said the passenger admitted having consumed alcohol.

Bulgarian Prime Minister Boiko Borisov praised the security forces' reaction.

"You saw how quickly our forces in Burgas acted after an absolutely false signal," he said. "Such a big concern because of a drunken Pole ... but still it was a kind of training."

Bulgaria has tightened controls at borders and airports since Friday's attacks in Paris in which 129 people died.