Germany's parliament building has closed its popular cupola to visitors amid heightened security.
The Reichstag's panoramic viewing area, which attracts up to 10,000 people a day, will be shut until further notice.
Other security measures around the building, visited annually by about one million, have also been increased.
Germany's Der Spiegel magazine has reported the discovery of plans by al-Qaeda linked militants to break into the Reichstag and take hostages.
A spokeswoman for the parliament building told the BBC that guided tours for visitors would continue, despite the alleged threat.
BBC News
