LONDON — A Ryanair Manchester-bound plane was evacuated before takeoff due to suspicious behaviour. While hours earlier, a security alert triggered by a fake bomb left behind at Manchester United’s stadium prompted evacuation of the stadium.

A Ryanair plane headed for Manchester, Britain, was evacuated before takeoff Sunday due to a bomb scare at Rygge airport outside Oslo, police said.

The plane was evacuated due to the “suspicious behaviour” of two passengers and a bomb squad searched the aircraft but found nothing suspicious. Police later said the incident was due to a misunderstanding.

Police spokesman Anders Stroemsaether told public broadcaster NRK that the incident started before boarding when two foreign passengers were overheard arguing in an airport lavatory. He said other passengers heard the word “bomb” being used and told the captain as they boarded the aircraft.

The captain informed police who evacuated the plane and brought the two passengers in for questioning.

Police said on Twitter later Sunday that nothing suspicious had been found at the airport and the two passengers were discharged.

“After questioning of witnesses and those brought in, the police have concluded that the situation is a result of a misunderstanding,” police said.

Rygge Airport is about 65 kilometres (40 miles) from Oslo.

The incident came hours after a fake bomb was found at Manchester United’s football stadium, prompting police to call off a Premier League match.

The discovery of the dummy bomb on Sunday prompted the evacuation of Manchester United’s stadium, Old Trafford. Police say the device discovered in a toilet just before kickoff had been left by a private company after a drill using search dogs.

Mayor Tony Lloyd described the incident as a “fiasco” that put people in danger.

Police initially described the device as “incredibly lifelike” and cancelled United’s match with Bournemouth.

Sunday’s evacuation came amid tightened security at Premier League stadiums following last year’s Paris attacks that targeted the Stade de France stadium as well as cafes, bars and a concert hall.