Detroit -

The National Highway Traffic Safety Administration is investigating reports of fires in the driver's side doors.

Affected are 2007 Toyota Camry sedans, Solara coupes, and RAV-4 crossover SUVs. 

On its website, NHTSA says the fires appear to start in the power window switch on the driver's side door.  Six fires have been reported. No one has been hurt.

More than 800,000 vehicles could be involved in the investigation, which was opened Monday.  No recall has been issued as of right now.

The Toyota Camry is the top-selling car in the U.S.