Police say they have sealed off part of the Dutch parliamentary complex and arrested a man who was acting suspiciously and left a backpack on the ground.
An explosives expert was called to check the backpack.
The arrest happened Friday while the Dutch Cabinet was holding its weekly meeting in one of the buildings that make up the Binnenhof, or Inner Court. The Cabinet meeting was not interrupted by the police action.
Hague police say in a tweet that part of the Binnenhof is closed while investigations continue. Further details were not immediately available.
The area is heavily guarded and normally members of the public can walk and cycle freely through the area.