Dallas - Dallas police say a U.S. Postal Service worker has been found shot to death inside a mail truck along a busy highway.

Police released a statement Monday saying the case is being investigated as a homicide.

Police say officers found the worker’s body inside the government vehicle early Monday morning after responding to a reported shooting along Interstate 30 near downtown Dallas. The U.S. Postal Service operates a large complex nearby.

Investigators say no arrests have been made and that they’re still trying to determine a motive in the shooting.

The victim’s name hasn’t been released.

Messages left by The Associated Press for representatives of the U.S. Postal Service weren’t immediately returned on Monday, a federal holiday.