A training weapon fell Wednesday morning from a Nellis Air Force Base aircraft and a piece of it struck a truck traveling south on Las Vegas Boulevard.
No one was injured in the 11:30 a.m. incident.
The weapon, known as a bomb dummy unit, fell on Nellis property and broke apart on impact, base officials said. A piece of the training weapon then bounced from the base onto Las Vegas Boulevard, near Beasley Avenue.
The 25-pound device is regularly used to simulate the ballistics of real air-to-ground weapons and does not carry explosives. It carries a small smoke charge, which is used to mark its impact point.
Nellis officials and Las Vegas police are investigating the incident.