A vacant Manhattan building that played a part in an infamous Gilded Age murder case partially collapsed Saturday night, less than two weeks after city officials expressed concerns about the building's stability.

No one was hurt as the back of the four-and-half-story building caved in at about 8 p.m., Buildings Department spokeswoman Robin Brooks said. Firefighters said the front facade was still standing, but the rear of the building was in rubble.

Witness Shane Hathaway said the collapse sent a plume of dust swirling around the building, at 22 W. 24th Street in the Flatiron neighborhood,

"The whole place was shaking, in a way. We thought it was a bomb," he told WCBS-TV. Nearby streets were blocked off as crews worked to clean up the area.

The building became a salacious footnote in a sensational 1907 trial involving a teenage showgirl, a jealous husband, and renowned architect Stanford White. He designed the original Madison Square Garden, the famous arch at Washington Square Park and several other city landmarks.

White rented part of 22 W. 24th St. and used it for trysts in 1901 with 16-year-old showgirl Evelyn Nesbit. She subsequently married, and her vengeful husband, Harry Thaw, shot and killed White on Madison Square Garden's rooftop garden in 1906. The trial revealed that White's 24th Street hideaway was outfitted with a red velvet swing, among other racy details. Thaw was eventually acquitted on the grounds of insanity.

In 2003, a fire swept through the building's second and third floors.

Buildings officials issued citations for failure to maintain the building exterior on Oct. 15, after the Fire Department asked for a check on the structure's stability, Brooks said in a statement. The agency ordered an adjacent parking lot to be partially vacated as a precaution, she said.

An owner of the building listed in city property records did not immediately respond to a telephone message and fax Saturday night.

No construction work was ongoing at the mixed-use building, and no permits had been requested, according to Buildings Department records, Brooks said.