A Ryanair passenger plane made an emergency landing in Berlin before resuming its journey to Poland, German police said late last night without releasing further details.

The flight from Dublin to Krakow made the unexpected diversion after a reported bomb threat, German newspaper Bild Zeitung said.

With 160 people on board, the flight arrived at the Berlin-Brandenburg airport shortly after 8pm (7pm Irish time), remaining on the tarmac into the early hours of this morning.

A Berlin police spokesperson said that officers had completed their security checks "without any danger being detected".

"The passengers will resume their journey to Poland on board a spare aeroplane," she told AFP, without giving more precise details for the alert.

The flight was emptied with the baggage also searched, German media reported.

"The Ryanair plane that made an emergency landed reported an air emergency and was therefore immediately given a landing permit at BER," airport spokesman Jan-Peter Haack told Bild.

"The aircraft is currently in a safe position," a spokeswoman for the police told the newspaper.

In a statement, Ryanair apologised for the "unavoidable delay, which was outside the airline's control".

It added: "The crew on a Ryanair flight from Dublin to Krakow FR1901 … were notified by German ATC of a potential security threat on board. The captain followed procedures and diverted to the nearest airport, Berlin.

"The aircraft landed safely and passengers were offloaded to facilitate extensive security checks of passengers and all baggage.

"Once cleared by German authorities, passengers travelled onwards to Krakow on a spare Ryanair aircraft after a delay on the ground of approx seven hours."

The incident comes a week after a Ryanair flight was forced to divert to Belarus, with journalist Roman Protasevich arrested on arrival.

In July last year, another Ryanair plane from Dublin to Krakow was forced to make an emergency landing in London after a false bomb threat.