Three people were injured Tuesday along I-5 in Washington state when a motor home careened into the rear of an SUV and a semi after the driver's brake foot allegedly became entangled in a floor mat, The Columbian reported.

The 81-year-old driver, David Hagerbaumer of La Mesa, CA, was driving a 28-foot 1993 Damon motor home north on I-5 about 11:05 a.m. when he pulled into the exit lane for the Gee Creek rest area north of Vancouver.

In his path were a 1991 Toyota Land Cruiser and a tractor-trailer driven by Jorge Galvan-Pineda. The Toyota and truck reportedly slowed on the exit, but Hagerbaumer's foot allegedly became entangled, and he was unable to brake.

The motor home smashed into the Toyota's rear, knocking it off the roadway. The motor home then rear-ended the semi's trailer, lurched off the road and slammed into a tree.

Hagerbaumer's wife, Delphie, who suffered broken bones, was the most seriously injured, according to the newspaper. The trucker was not injured.

No citation reportedly was issued at the scene, but the case is under investigation.