Two BASE jumpers were caught on camera parachuting off a Downtown Pittsburgh skyscraper. 

Pittsburgh police shared photos of the two men on Tuesday, saying they're investigating the incident that happened shortly before 5 a.m. on April 9.

Police said the two men entered 1 PPG Place near Stanwix Street and Third Avenue and made their way to the rooftop, where they jumped off, using parachutes. Police shared photos of them landing and getting into a black pick-up truck afterwards. 

The two men were captured on surveillance footage wearing black clothes and beanies. 

PPG Place describes itself as the "crown jewel" of Pittsburgh's skyline. 

Detectives from the Downtown Public Safety Center are investigating. Police didn't release any other details.   

Is BASE jumping legal? 

Cecil Smith owns Sky Dive Pennsylvania at the Grove City Airport. It's a business that hosts thousands of jumps every year all over Pennsylvania. When asked about BASE jumping in general, he told KDKA-TV, "The majority of base jumps made are illegal."

"When I hear people make a BASE jump from Downtown Pittsburgh, the first thing, I'm a little bit entertained, but I sure hope that nobody got hurt or arrested, because sometimes they do catch them and they do arrest them," he says.

There are different types of jumps. Skydiving is legal just about everywhere and BASE jumping is only legal in a fraction of U.S. sites. The difference?

"Skydiving is always done from something in flight," Smith explains. "A hot air balloon, a helicopter or an airplane. That's skydiving and that's what's governed by the United States Parachuting Association. BASE jumping is not really governed, it's governed by themselves. It's not regulated."

"The are some legal places like Moab, Utah, and the Perrine Bridge in Utah, but there's not many places where you can make a legal parachute jump," he said. 

The most common law broken during base jumping is trespassing, with thrill seekers going where they shouldn't. But where it is legal, there are huge events. 

"The most one made is at the New River Gorge Bridge, the third Saturday in October," Smith says. "They open that bridge up for base jumping."

"And that's legal?" Barry Pintar asked.

"That is legal," Smith said.

"Is there anywhere in Pennsylvania to legally base jump?" Pintar asked. 

"No," Smith replied.