The United States government has opened an investigation of complaints that side air bags on some Ford Lincoln Town Cars deploy inadvertently, Reuters reported.

The National Highway Traffic Safety Administration said it had received 138 complaints that air bags on 2001-2003 Town Cars deployed while the car was moving or after the vehicle ran over a pothole, gravel or debris, the report added.

Inspections by dealerships or Ford found either minor undercarriage damage or no evidence of impact, Reuters said.