Two elderly District residents recently answered the knock at their apartment doors by a man saying he was from building maintenance. The stranger outside pushed his way in, tied them up and ransacked their possessions, police said.

D.C. Police Chief Cathy Lanier issued a public warning Wednesday that police are investigating two similar cases, one in Northeast and the other in Southeast, this month where the victims were assaulted, restrained and robbed of cash and property. Neither victim sustained any serious injuries, Lanier said.

“We want to make sure our senior residents are aware that we’ve had this issue. If someone knocks on your door and claims that they are maintenance, I would not open the door,” Lanier said at a news conference. “The fact that we’ve had two of these, obviously gives us extreme concern.”

Police released surveillance video of a “person of interest” in the first case, which occurred June 19 in an apartment building in the 1400 block of Florida Avenue NE. The man is in the building lobby.

The second incident happened Tuesday in the 1200 block of G Street SE, police said.

Both incidents happened in the afternoon or early evening, officials said. Investigators said the suspect in both cases had a similar description, a black male, about 5’7”to 5’8” tall with a medium build.

Anyone with information is asked to call police at 202-727-9099.

This Post has been updated.