Police say the Eiffel Tower has been evacuated after an anonymous caller phoned in a bomb threat.

A Paris police official says nearly 1,400 people have been evacuated following a request from tower operators after the warning Saturday. Police then searched the monument with sniffer dogs for possible explosives, and set up a broad security perimeter.

French authorities have stepped up counterterrorism measures in recent weeks amid heightened concern about threats to France over its military campaign against al-Qaida-linked fighters in Mali which began more than two months ago.

The tower is occasionally evacuated because of such warnings _ at least once last year and twice in 2011. The 324-meter (1,063-foot) tower is one of the world's top tourist attractions, with millions of visitors a year.