Tourists visiting the Eiffel Tower in Paris were evacuated from the iconic landmark following an anonymous phone call announcing an attack on Saturday night.
Police told AFP around 1,400 people were visiting the site when it was cleared and a security perimeter was set up around the monument.
L'Express news website said that tourists and staff were told to come down from the tower at around 7pm on Saturday.
Security guards were also ordered to leave, a decision which was described as unusual.
Anti-terrorism police searched the area for several hours with sniffer dogs for possible explosives.
The call reportedly came from the Paris suburbs and threatened an attack at 9.30pm.
The anti-terrorism unit is investigating.
Bomb alerts targeting tourist attractions and public spaces happen frequently in the French capital and the Eiffel Tower has been targeted several times in recent years.
A police source told AFP that all alerts are "treated very seriously".
The BBC reports that security across France has recently been stepped up amid concerns about threats over its military campaign in Mali.
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