U.S. probes Lexus sudden acceleration

DETROIT– The U.S. federal government has upgraded an investigation into the 2007 Lexus ES 350 sedan after at least 12 people were injured when the vehicle accelerated without warning.

An all-weather floor mat can trap the throttle pedal when it's not properly secured, resulting in unwanted acceleration, the U.S. National Highway Traffic Safety Administration said in a report.

Toyota said it mailed ES 350 American owners in April warning them about improper installation.

Because the investigation is ongoing, it's too early to say whether floor mats are definitely causing the alleged defect, a Lexus spokesperson said.