DETROIT -- Drivers of the Hyundai Veloster could be in for a surprise while cruising down the highway.
The panoramic sunroof on the funky hatchbacks can shatter without warning, showering the driver with glass.
U.S. safety regulators are investigating the problem, although they have not recalled the cars. The probe affects about 18,000 vehicles from the 2012 model year, the National Highway Traffic Safety Administration said Friday.
So far, 11 drivers have complained to NHTSA about the panoramic roofs shattering. Seven said the cars were moving.
Shattering glass could distract the driver and injure people in the car, the agency said. A few people complained of minor scratches from the glass, but there were no reports of crashes, according to NHTSA.
NHTSA investigators will figure out whether the problem is bad enough to require a recall.
Hyundai said it is working with NHTSA on the investigation. The complaints involve only a small percentage of Velosters on the road, so it's not necessary to get the cars inspected, spokesman Jim Trainor said.
In one complaint, a driver was making a left turn on Aug. 3 when there was a loud bang and the sunroof shattered.
"I had shards of glass in the top of my head, back down the inside of my shirt, and the glass still hanging was flying off," the driver reported.
NHTSA does not identify drivers who file complaints.