A cordon of police officers and private security stood guard Friday in front of The New York Times building after two daredevils scaled the skyscraper in midtown Manhattan within hours of each other.

Police arrested both men Thursday after each safely reached the top of the 52-story tower, the distinctive facade of which has slats like the rungs of a ladder.

The stunts drew the attention of hundreds of onlookers, along with TV cameras that captured the drama in real time. Crowds on the street pressed against police barricades to watch the climb, and people clapped and cheered while snapping pictures on their cell phones.

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The first man, French stuntman Alain Robert, unfurled a banner as he climbed that said "Global warming kills more people than a 9/11 every week."

Hours later, a Brooklyn man, Renaldo Clarke, made his own ascent up the building, saying that he wanted to promote awareness about malaria.

Neither man wore a rope or harness.

Both were charged with reckless endangerment, criminal trespass and disorderly conduct, and Robert also was charged with making graffiti for posting the banner about global warming on the side of the building.

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Robert was released on bail early Friday and Clarke was awaiting arraignment.

Police said the officers became concerned that Clarke might be an emotionally disturbed copycat, and he was taken to a hospital for a psychiatric evaluation before being returned to police custody.

Robert's Web site says he has climbed more than 70 skyscrapers around the world including the Eiffel Tower and Louvre Pyramid in Paris. He was arrested in February after climbing a 42-floor building in Sao Paulo, Brazil.

The stunts were staged at the Times building, just a block south of the busy intersection of Eighth Avenue and 42nd Street, across the street from the Port Authority bus terminal.

A spokeswoman for the Times, Catherine Mathis, said the climbers threatened the safety of themselves and others, and that no one at the newspaper knew of plans for the climbs.

Reacting to the content of Robert's banner, Mathis said the Times has "a very green building."

She said the ceramic slats save energy by reducing the amount of heat and light entering the building, where the Times moved last year.

Clarke's Facebook page says he enjoys climbing and lists "xtreme living" among his interests. The page identifies him as an information technology support manager for a Manhattan advertising agency. He did not immediately return an online message.

A Facebook friend, Catherine Zubkow, said Clarke is a seasoned climber and is not emotionally disturbed.

"He would never intentionally try to harm anyone," she said via e-mail. "It is possible he did not foresee all the consequences of his actions with regards to the law."

New York's skyscrapers have long attracted high-rise stunts.

In 1974, French artist Philippe Petit made a daring and illegal wire-walk between the twin towers of the World Trade Center. British director James Marsh made "Man on Wire," a retelling of the derring-do.

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