The Eiffel Tower has been evacuated after a person was spotted climbing up the Paris landmark, the company that operates the structure said.

A person could be seen dangling just below the third and highest level of the structure. A rescuer dressed in red was just above him.

“A climber has been spotted. It’s the standard procedure: We have to stop the person, and in that case we evacuate the tower,” an SETE official said.

“We kindly advise our visitors to postpone their visit,” the SETE added on Twitter.

Police said the climber was a male.

It wasn’t immediately clear how the trespasser managed to get past the stringent security system.

The esplanade underneath the monument was also evacuated.

Social media exploded with reports of the incident. “Why would you lcimb up the Eiffel Tower?” one person demanded to know.

“Just having a picnic in the park when we notice there is literally a guy dangling from the Eiffel Tower,” another said.

Police have made contact with the climber but do not yet know why he began his ascent via the iron beams, a police source told AFP.

At around 5.30pm (1.30am AEST) firemen were trying to reach the climber, dressed in a black jacket, by rappelling down from the third-floor observation deck near the top.

Crowds of tourists remained in the area, hoping the tower will reopen soon. “We’re really disappointed, we’re only here for a week and this messes with our whole program,” said Sylvie and Celine Forcier from Quebec.

Justin and Karen Smith, from Los Angeles, had celebrated their wedding on Sunday in front of the tower, but were hoping to get to the top on Monday (local time). “We’re disappointed,” he said.

The tower is regularly the target of rogue freeclimbers hoping to scale one of the world’s most famous structures, often for bragging rights.

But police have also been called in several times in recent years to try to thwart suicide attempts.

In October 2017, a young man ventured out on one of the beams and threatened to jump before police were able to convince him to come back.

In 2012, a British man managed to climb to the very top of the tower before plunging to his death.

The first two floors can be reached by either elevator or stairs, but only elevators whisk people to the top observation deck.

That did not stop the French urban freeclimber Alain Robert from making it one of his first targets in his campaign to scale the world’s biggest buildings with no technical climbing gear.

He got to the top — not including the antenna — in the mid-1990s.

Nearly seven million people a year visit the 324-metre-high structure, which last week celebrated its 130th anniversary.