A well-known sports climber scaled the Millennium Tower on Mission Street in San Francisco on Monday afternoon without ropes, climbing equipment or permission, before he was arrested by San Francisco police on the roof of the building.

Police say Dan Goodwin, also known as "Spider Dan" started his ascent around 2:15 p.m. He now calls himself "Skyscraperman," and is known for climbing some of the tallest buildings in the U.S., including the Sears Tower, John Hancock Center and World Trade Center.

He uses a sophisticated suction cup system to climb many of these buildings. He said he wants to show the vulnerability of skyscrapers and also call attention to cancer, as he is a cancer survivor.

The 54-year-old, who now lives in Lake Tahoe, scaled the 58-story building in a little over three hours.

Police had to shut down Mission Street between Fremont and Beale streets near the building as a precaution. Fire crews were also on the scene.

Goodwin reportedly ignored orders to stop climbing the building.