The Eiffel Tower evacuated some 1,500 people tonight after a telephoned terrorist bomb warning sent the police into high alert.

The 1,500 people escorted out the world-renowned landmark include tourists and staff. They were assisted to leave the premise around 7:30 p.m.

The threats followed a series of warnings from Al-Qaeda pledging “revenge” for the French intervention in the African state of Mali to fight Islamic terrorists.

French police said that the anonymous phone call came from a phone booth in a Paris suburb. It warned that explosives had been placed around the tower.

The bomb warning said that the blast would happen around 9:30 p.m., according to the police. But by 10 p.m., local time, there had been no explosion.

“It may be that the tower does not reopen tonight,” said a spokesman from the police department. They also said that “‘Searches are carrying on, but no members of the public are being allowed anywhere near. There has been a full evacuation.”

The tower is usually open until midnight during the Easter weekend, and nearby restaurants like Le Jules Verne are particularly busy on a Saturday night.

A police cordon was formed around the tower and the tourists and staff evacuated were moved to the banks of the nearby River Seine.

There have been numerous bomb alerts at the Eiffel Tower in recent years, and France is currently on an increased state of vigilance following threats from Al-Qaeda in the Islamic Maghreb.

The country’s President Francois Hollande has placed himself at the center of the global war against terrorism, after committing French troops and airpower to the on-going war in Mali.

The president has also stepped security in mainland France due to the constant threat and fear of an Islamic extremists’ strike against the country.

The 1,050ft tall iron lattice tower was built for the 1889 World’s Fair. It has become a prestige symbol of modern France and a global landmark.

It is also the most visited paid-for monument in the world, attracting some 7 million people annually.

It’s high profile and high-traffic of people, locals and tourists alike, is key reason why French security officials highlight the vulnerability of the tower to terrorist attack.