CUMBERLAND – A South Portland woman is recovering after a chain reaction sent her car flipping into and over oncoming traffic on Interstate 95 Monday, causing a major traffic backup.

The five-car accident led police to detour commuters onto Route 1 for an hour and a half after the 7:30 a.m. crash.

Traffic came to a standstill from just south of Exit 16, where the accident occurred, to Exit 19 in Freeport.

Claire Hammond, 60, was driving her 1997 Honda Accord northbound when a wheel came off a pop-up trailer several cars in front of her. A car following the trailer collided with the errant wheel, which dislodged that car’s bumper.

Hammond swerved to avoid the bumper, driving down into the center median. The front end of her car hit the low point in the median and flipped the vehicle through air, colliding head-on with a 2003 Saturn rental car in the southbound passing lane.

The couple in the Saturn, Herman and Kathryn Kuebler, received minor injuries.

After the head-on collision, Hammond’s car flipped over the oncoming cars in the travel lane before landing on the grass alongside the southbound breakdown lane.

The small tire that started the sequence also went flying across the median and slammed into an oncoming tractor-trailer truck, damaging the grill.

The accident is still under investigation.