TPD says both people in the unmarked car are officers, one of whom was on duty while the other was not. EMSA took the driver of the car and her male passenger to a hospital with serious injuries.
Police said the driver had slowed for traffic that was backing up in the southbound lanes because of ODOT repair work.
She saw the dump truck approaching from behind and realized it wasn't going to stop in time so she took evasive action. The dump truck hit the car, turning it 180 degrees and smashing it against the center divider near the 31st Street exit.
News On 6 reporter Erin Conrad said the crash spread glass and debris for quite a ways in the southbound lanes, indicating the truck must have dragged the car for some distance.
The wreck forced police to close the inside lane of southbound 169 near the 31st Street exit. Traffic in the northbound lanes was moving slowly, too.
The driver of the dump truck wasn't hurt. Police wrote him a ticket for excessive speed.