A pilot on an Air Europa aircraft triggered a major security lockdown at Amsterdam's Schiphol airport on Wednesday after accidentally setting off an alarm, the airline said.
The warning set off hijack procedures at the airport, as rumours surrounding the incident swirled on social media.
"In a plane from Amsterdam to Madrid tonight an alarm was accidentally activated, which set off safety protocols at the airport," it said.
"There was no cause for alarm. All passengers were fine and waiting for the flight to take off.
"We are sorry. There was no cause for alarm."
Dutch military police said all 27 passengers and crew were safely taken off the plane during the security alert.
Police had said they were investigating a "suspicious situation" on board the aircraft.
The Royal Netherlands Marechaussee is currently investigating a situation on board of a plane at Amsterdam Airport Schiphol. We keep you posted. https://t.co/AxwMZ7CZtT
— Schiphol (@Schiphol) November 6, 2019
Local media reported the emergency services were massing at the airport on the outskirts of Amsterdam.
Witnesses said police were on standby near the aircraft and two helicopters were flying over the airport.
Photographs posted on social media showed areas of the airport closed off with tape.
Schiphol. pic.twitter.com/Vfa321xUEH
— peter vandermeersch (@pvdmeersch) November 6, 2019
There were significant delays to flights leaving the airport and inbound flights were allowed to land but being held back from the arrival gates.
“The situation is now safe,” airport spokesman Dennis Muller told The Associated Press. “All flights can now depart.”
The local mayor responsible for the Schiphol region, Marianne Schuurmans, said it took two hours to give the all-clear signal.
“Further investigation by the military police must determine exactly what happened,” Ms Schuurmans said.
Willem Schmid, president of the Association of Dutch Pilots, said there are two ways a pilot can raise the alarm in a hijacking situation — via the plane’s radio or by entering a code in its transponder, a device that communicates with air traffic control.
“Which was used and why, let’s investigate that so we can learn from it, so it doesn’t happen too often,” Schmid said in a telephone interview.
Dutch Justice Minister Ferd Grapperhaus said in a tweet that he was impressed by the “sharp and alert response of authorities and services, both local and national.”
Schiphol is one of Europe's busiest airports, handling more than 70 million passengers every year, according to its website.
The alert in the Netherlands came as Milan’s Malpensa Airport was briefly closed while police investigated a suspicious item in someone’s luggage that turned out to be a harmless computer part. Flights were taking off and landing normally during that time.