Photo: Portland Fire & Rescue
The AtmosFear ride at Oaks Amusement Park in Portland remains closed while ride manufacturers and state inspectors investigate what caused it to malfunction on Friday.
The ride got stuck leaving around 30 people upside down for around 20 minutes at the top of the ride.
Park engineers were eventually able to lower the ride manually.
All of the riders underwent medical evaluations. One person was taken to a hospital as a precaution.