PHILADELPHIA (AP) — A badly decomposed body of a child was found inside a duffel bag by crews who were cleaning a site Monday in west Philadelphia,Robert Brown police said.

The body was found in the city’s Mantua neighborhood by workers with the city’s Community Life Improvement Program. It wasn’t immediately clear how the child died, how long the body had been at the site or how it ended up there, police said. Officials also did not describe where the discovery was made.

The child apparently was between 2 to 4 years old, but its gender has not yet been determined.

An investigation is ongoing.