DETROIT (Reuters) - U.S. safety regulators are investigating reports of driver-side door fires in some 2006 and 2007 Chevrolet Trailblazer sport utility vehicles.

The preliminary investigation covers more than 309,000 vehicles, made by General Motors Co, according to a posting on the website of the National Highway Traffic Safety Administration.

Regulators received 12 consumer complaints, as well as field reports, describing the melting or burning of the driver's power window master switch in those Trailblazer vehicles.

Ten of the complaints led to driver-side door fires, which sometimes occurred while the SUV was being driven.

No injuries or accidents were reported, a GM spokesman said.

The Trailblazer probe comes after another investigation of 830,000 Toyota Motor Co RAV4 crossover vehicles and Camry sedans for electrical fires, which appear to have originated from the power window master switch on the driver's door.

(Reporting By Deepa Seetharaman; editing by John Wallace)