ASYLUM

In an apparent recording of a radio communication between the aircraft and air traffic control posted on the social media site Twitter, a demand for asylum was made.

"We need asylum or assurance we will not be transferred to the Ethiopian government," the voice in the recording said, posted by Twitter user @MatthewKeysLive.

A flight tracking app for mobile devices showed the flight circling over the Swiss city several times before landing.

Ethiopian nationals and the Horn of Africa country's flag carrier have been involved in several hijackings in the past.

In 1993, an Ethiopian used a gun hidden in his hat to hijack a German passenger jet bound for New York. He was later sentenced to 20 years in a US prison.

Two years later, police in Greece overpowered an Ethiopian hijacker who held a knife to the throat of an Olympic Airways stewardess and demanded political asylum.

At least 50 people were killed when a hijacked Ethiopian Airlines passenger jet crashed in the Indian Ocean in 1996. In 2001, a dozen Ethiopian students hijacked a plane carrying around 60 people and flew to Sudan.