The remains of a small child were found Monday inside a trash receptacle in a restroom in a building in Northwest Washington, authorities said.

The remains were found in a plastic bag inside a receptacle in a unisex lavatory in a building in the 100 block of Irving Street NW, D.C. police said.

It was not clear whose remains they were or how they came to be there.

A spokeswoman for a medical office building at the site confirmed that the remains of a baby were found there about 7:40 a.m. She expressed deep sadness at the tragedy and said efforts were being made to aid in the investigation.