The plane, flown by Spanish carrier Vueling (VULG.MC) from Malaga in Spain to Amsterdam with about 180 passengers on board, had lost radio contact with air traffic control, a spokesman for the military police told Reuters.

"There was no communication with the crew at all," Martijn Peelen, military police spokesman, said. "My colleagues are still talking to the (plane's) captain to find out what caused the communication failure."

Peelen said that as soon as the plane landed at Schiphol airport, it was surrounded by security forces and a negotiator was sent to talk to the crew.

"After the negotiator spoke to the captain we were certain there were no hijackers on the plane," Peelen said.

The plane had been intercepted and escorted by two F-16 fighters sent by the Dutch Defence Ministry.

"The scrambling of fighter jets was part of a standard emergency procedure after the plane failed to communicate," said an official of the NATO Western military alliance. NATO's Combined Air Operations Centre had notified the Dutch military after being alerted by air traffic controllers to the loss of contact.

Passengers had to remain on board the plane for hours while it was searched by police, but were later allowed to disembark and board buses.

"We first realized something was wrong when we started circling above Rotterdam over and over, and the captain told us there was some problem in Schiphol. We spent about four hours on the ground after arriving," said Erna, a passenger, who asked that her surname not be used.

A spokeswoman for the airline, Vueling, said: "There was never any danger. There was a lack of communication between the pilot and the tower and the airport has activated the security protocol." (Reporting by Ivana Sekularac, Thomas Escritt, Gilbert Kreijger and Madrid Newsroom; Editing by Peter Graff)

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