There’s a widespread belief that big-city residents keep to themselves and care little about anything beyond their doorstep. But on Monday afternoon in Northwest Washington, someone apparently depended on that presumption too much.

In midafternoon, police said, a resident of the Shaw area saw a man entering a house in the 900 block of T Street through a window.

In addition to the unconventional mode of entry, police said, something else aroused the neighbor’s suspicion. The neighbor knew that the man did not live in the house, police said. The police were called.

They said they found somebody in the area “running to elude capture,” and were able to apprehend him without incident. No information on any charge was immediately available.