The Cedar Point roller coaster accident that injured three was probably caused by slickened rails due to last weekend's wet weather, an amusement park spokesman said.

The accident happened on Saturday on the Magnum XL-200 roller coaster when a train moving at less than 10 mph failed to stop completely in the braking area, and struck another train waiting in the holding area.

The ride reopened on Sunday with one train, spokesman Tony Clark said. Maintenance staff are making repairs to the ride's other two trains, both of which suffered minor fiberglass damage in the accident, he said.

Inspectors from the Ohio Department of Agriculture's amusement ride safety division have determined that the ride is safe to operate with one train, department spokeswoman LeeAnne Mizer said.

Two injured riders were treated at a First Aid station on Saturday before returning to the park, and a third person involved in the accident was taken to a nearby hospital for treatment after suffering an asthma attack.