State workplace safety investigators are looking into an incident in which a Disneyland worker was left seriously injured after being hit by a car that's part of the popular Space Mountain attraction.

The 68-year-old machinist was struck just before 10 p.m. Oct. 3 while he was testing a vehicle that's part of the Space Mountain ride, according to the California Division of Occupational Safety and Health, or Cal/OSHA.

The worker was identified as Christopher Monday, of Lakewood, by Sal Vasquez, a business representative with the International Association of Machinists & Aerospace Workers, the union that represents machinists at Disneyland. The union is cooperating with the Cal/OSHA investigation, Vasquez said.

A Disneyland spokeswoman said the worker was hit by the kind of vehicle that theme park guests ride in. The indoor roller coaster, part of Tomorrowland, opened in 1977.

"Our thoughts and prayers are with our cast member and his family. On behalf of his fellow cast members, we offer our heartfelt wishes for a full and speedy recovery," Disneyland spokeswoman Suzi Brown said in a statement.

The Space Mountain ride was not in operation at the time of the incident and the Anaheim park was closed, according to Erika Monterroza, a spokeswoman for Cal/OSHA. The employee was struck when he was testing a vehicle that had just come back from "rehab," where it was being maintained, Monterroza said.

OSHA's Peter Riley said the ride would not have reopened if there were evidence to suggest it was unsafe.

The man was injured in the back, chest and head, Monterroza said. The incident was reported to Cal/OSHA in accordance with state requirements, she said.

The employee was in critical condition Tuesday, according to the Orange County Register, which first reported the incident.

State accident-initiated workplace investigations usually take 3 1/2 to five months to complete, Monterroza said.

Space Mountain has been open since the day after the incident. Peter Riley of Cal/OSHA said the ride would only be reopened if it had been deemed safe for the public to ride.

NOTE: Cal/OSHA's spokeswoman originally reported that Disneyland was open at the time of the incident. The park had closed at 8 p.m. that night, Erika Monterroza later said. The story has been updated to reflect that.