A strip club and two other buildings collapsed in northwest D.C. Friday afternoon, sending patrons and dancers into the streets.

Some inside the club were forced to jump out of second-story windows as the buildings' floors pancaked into each other.

"[We were] just dancing, doing our routine ... and the wall collapsed in on the kitchen and the bathroom. Some of the girls were shaken up," Olivia, a dancer at The Cloakroom, told News4.

No serious injuries were reported, though one person was transported to a local hospital.

Witnesses described panic on a stretch of K Street packed with bars and restaurants. "There were three guys that got out of there," said Ryan Multer, a witness, pointing to the rubble from across the street. "And there was a woman -- you could see she was on her cell phone -- and she was going back and forth on her cell phone in there in distress, but she eventually got out.

"We didn't know what was going on," Multer said.

The buildings are located in the 400 block of K Street NW. The first collapse happened around 3 p.m. and appeared to involve in a red brick building for sale, as well as the building next to it.

That building houses The Cloakroom, which bills itself as an "adult entertainment" venue. The club opened at noon Friday, and had eight dancers scheduled to perform a noon through 7 p.m. shift.

"I was eating lunch over here with my girlfriend, and we saw about five people exit the middle window, the second story window," said another witness, who would not give his name. "They jumped out. There's a smaller roof right beneath it so it didn't look like they got hurt when they jumped out."

Then, about an hour later, another collapse tore down part of the exterior walls of The Cloakroom and nearby buildings. Widescreen TVs could still be seen clinging to the interior walls of the club.

That second collapse was a close call as well. A team of D.C. firefighters and rescue personnel -- including a search dog -- had been searching the building moments before the second collapse, and left through the back of the building just before the walls came down.

A wall of bricks scattered onto the sidewalk where entertainers had been sitting moments before after they had been evacuated.

According to the Department of Consumer and Regulatory Affairs (DCRA), construction work was being done in the basement of The Cloakroom when the first collapse happened. Workers on Bobcats were doing foundation work, and officials tell News4 buildings should be vacant when that type of work is being conducted. DCRA is now investigating whether the work being conducted Friday was properly permitted.

An Advisory Neighborhood Committee representative for the block told News4 there had been complaints about "blight" and "disrepair" of the brick building attached to The Cloakroom, filed by residents of the city.

Last month, local blog PoPVille.com noted in a blog post that large cracks seemed to be forming in the building.

"They don't always rush out; I guess they hear a lot of complaints and they have to prioritize which ones are the most important," said Marge Maceda, the ANC representative. "But when something like this happens, it's time for them to look at all the things that people send them and make sure that they at least send somebody out and look at them and take action.

The News4 I-Team has learned the city issued The Cloakroom's building's owners an "alterations permit" in November 2012, which included structural work. City inspectors are investigating the scope of those renovations.

The building had previously housed Louis' Rogue Club, which closed in 2011 for renovations.

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