Ground crew staff at Stockholm's Arlanda airport made a shocking discovery Monday when they found a stowaway hidden in a cargo container on a flight from Ethiopia, police said.

"Staff at Arlanda airport have found a man in a freight container on a flight that arrived from Ethiopia. The man ... has applied for asylum in Sweden," police said in a statement.

The cargo hold of most airplanes contains pressurised oxygen and while the temperature is generally cool, it is usually above freezing.

There was no immediate confirmation of the man's nationality or age, but Swedish news agency TT reported he was 27 years old.

In August 2014, an Ethiopian asylum seeker who stowed away aboard a flight from Addis Ababa to Stockholm was found safe and sound in the plane's hold at Arlanda airport.

A total of 174 Ethiopians were granted asylum in Sweden in 2015, representing 37 percent of those who applied, compared to 148 people and 33 percent the previous year, according to the Swedish Migration Agency.