A spokesperson for the airport said that the plaza, which contains bars, restaurants and shops was evacuated but the sections behind check-in desks and security were not evacuated.
In a Tweet, the police said the man was "known to police in connection with previous violent incidents". The police haven't confirmed whether the incident was related to terror.
"This afternoon a man came into the office of the Marechaussee [military police] here at Schiphol and threatened my colleagues with a knife", a police spokesman told AFP news agency. The "situation is now safe", the armed forces unit said. No details of the man's condition have been released by the police. "Air traffic is experiencing no further consequences", the tweet said.
TWITTER TreehouseTravlRSchiphol Airport was evacuated following the incident
The man was arrested and then taken to an Amsterdam hospital as police began investigations at the scene while travellers who had been ushered outside have been allowed back into the airport.
No further information was immediately available.
There are no reports of injuries and the airport - one of Europe's biggest - has now reopened.
Schiphol airport is one of Europe's top five busiest air hubs, handling a record 63.6 million passengers in 2016, up from 58 million in 2015.
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