At around 11 p.m. on Nov. 26, Ronald Thornton was watching a home improvement television show when he heard what sounded like a truck smashing at high speed into a building. Then he felt the floor tremble.

Thornton and his neighbors in Mount Vernon Square filed onto Ridge Street NW to see what had happened. Across from Thornton’s home, part of an abandoned two-story row house had crashed to the ground. Bricks lay scattered across the street. Some had tumbled against a home nearby. A side of the building was gone.

The collapse was the end of what neighbors say is a storied history at 460 Ridge St. NW. Neighborhood lore has it that the boarded-up house, which is owned by the District, has sat vacant since 2002, when crack smokers accidentally set it on fire.

It was “demolition by neglect,” says Cary Silverman, president of the Mount Vernon Square Neighborhood Association.

The fallen house is one of more than 100 vacant buildings in a seven-block radius in the neighborhood, many of which are owned by the District, Silverman adds. “All of these properties are a danger,” he says.