Police say an unidentified falling object dropped out of the sky with enough velocity to tear a hole through the roof and the second floor of a Dallas home.

Senior Cpl. Kevin Janse said Wednesday the six-pound piece of metal with two drill holes in it fell Tuesday evening when the person who reported the incident wasn't home. Janse said there were no injuries.

Officers couldn't determine the source of the debris. Janse said radioactive tests on the metal were negative. Several state agencies were notified of the incident, but Janse said none offered a theory about what happened.

Janse said there were no other reports of similar incidents in the Dallas-Fort Worth area.