Four base jumpers leap from 40-storey Perth tower

Four base jumpers have made a daring plunge off a 40-storey skyscraper in the heart of Perth.

The daredevils wore business suits to access the city building, and their dangerous stunt was caught on camera.

Four men dove off the edge of Exchange Tower in Perth's CBD just before 9am today.

"Everyone quite frantically got up and we saw a bunch of parachutists flying down," witness Piers Egerton-Warburton told 9News.

Stunned workers captured the daredevils from all angles, and even their getaway on foot was caught on camera.

"We saw the guys land just over here on the grass and they just sort of legged it across the street," witness Curtis Hesse told 9News.

Exchange Tower is a 40 storey skyscraper and it is the sixth tallest in Perth. It is unclear how they got into the 146-metre building, which is the state headquarters of the Australian Securities Exchange.

However, they were well prepared. Witnesses say they were wearing business suits which helped them blend in as they entered the building.

The building is home to several federal politicians, including Attorney General Christian Porter and Defence Minister Linda Reynolds.