PORTLAND, Ore. -- A malfunctioning door on a light rail train separated a 3-year-old boy from his father earlier this week in southeast Portland.

Aaron Bailey and his son were separated Monday at 8:13 a.m. at the Southeast Main Street station.

Surveillance video from TriMet, Portland's transit agency, showed the boy stepping off the train as he pushed the accessible ramp button on the door. This caused the door to open and then close again to deploy the ramp.

The door didn't reopen. A woman standing on TriMet's MAX platform pressed a button on the outside of the door but the door didn't open. Bailey was also pushing the door button from the inside of the train, but to no avail.

The woman on the MAX platform stayed with the child until Bailey returned on a southbound train from Gateway. The video showed Bailey running into the picture seven minutes after they were separated.

According to TriMet, Bailey said he pushed the intercom button inside the train to contact the operator but he received no response. Bekki Witt, a TriMet spokeswoman, said there appeared to be a malfunction with the audio component of the intercom.

Bailey and his wife received annual TriMet passes as part of the apology from the transit agency.

Witt said the malfunctioning door and ramp are still being investigated. She said the ramp deployment process may have been overridden, causing it to be interrupted.

TriMet's protocol for such incidents is for a train operator to contact TriMet's control center to report what happened. A supervisor is then dispatched to the child's location and stays with the child until he or she can be reunited.