The Eiffel Tower and the surrounding Champ de Mars park have been evacuated for the second time in two weeks after a bomb alert.

"The police asked us to evacuate, saying they had received a warning," a spokeswoman said.

Usually around 2,000 people were in the area at that time of day, she said.

A police spokeswoman said the fire service had received a call from a public telephone saying there was a suspect package at the tower. A witness at the scene said the police had cordoned off an area about 200 metres from the tower.

The bomb alert was the fourth in as many weeks. French security officials said last week the country was on heightened alert after receiving a tip-off of a planned suicide attack on the Paris metro.

Eariler this month, Interior Minister Brice Hortefeux said France faced a real terrorism threat as it faces a backlash from al-Qaeda militants in North Africa and fears grow of an attack from home-grown cells within its borders.