(CNN) -- Dutch security forces entered a plane at Amsterdam's Schiphol Airport on Wednesday in response to concerns about a potential security incident, a spokesman for the National Antiterrorism Unit said.
The alert, which also led to military jets being scrambled, was prompted by a loss of radio communications with the plane, spokesman Edmond Messchaert told CNN.
This "made us think that there could be a hijacking situation; we sent the two F-16 jets as a precautionary measure," he said.
Security forces concluded there appeared to be no threat to the flight after talking to a passenger on the plane, Dutch national TV reported.
The plane landed safely and was searched by military police. Messchaert said. "The military police have now finished their search and have released the aircraft," he said.
The alarm was prompted when the pilot took an unusual approach to the airport, one of the busiest in Europe, Dutch national TV reported.
Spanish low-cost airline Vueling, which operated the aircraft, also said a communications failure was to blame.
The airline's official Twitter account said: "The security protocol in Amsterdam was activated because of a loss of communication between the plane and the control tower."
Flights at Schiphol Airport were disrupted earlier Wednesday after construction workers discovered a suspected unexploded World War II-era bomb there.
Part of the airport was closed while a bomb squad investigated, a statement on the airport's website said.
CNN's Laura Perez Maestro, Mariano Castillo and Stefan Simons contributed to this report.