Officials found that human error was to blame for the Dec. 5 derailment just north of Atlanta, MARTA general manager Richard McCrillis said Wednesday.

A series of ``bad judgment calls'' were made after a northbound train stalled at the Medical Center station, McCrillis said.

A MARTA spokeswoman said a decision was made to put northbound and southbound trains on the same southbound track to get around the stalled train.

However, the rail system controller failed to notify the disabled train's operator, who briefly moved the train into a section of track being used for the rerouting, MARTA spokeswoman Joselyn Baker said.

The derailment happened after the train moved forward from the station platform. The front of the train entered a switched portion of track and stopped. When the train began to move back south toward the platform to offload passengers, the wheels ran off the rails, officials said.

The train was moving slowly, preventing any injuries.

The rail controller, whose name was not released, was fired, Baker said. And MARTA placed two train operators on unpaid leave for 15 days for moving the train without instruction from the rail control, which is a violation of policy.

``In that situation, there's supposed to be constant communication between operator and rail control,'' Baker said.

While the derailment did not cause any injuries, it did cause delays for much of the day.

Safety measures were automatically triggered when the malfunctioning train engaged the rail switch, stopping the northbound train before any collision could occur. But it was a close call that should never have happened, McCrillis said.

``It could have been much worse,'' he said as he gave MARTA's annual report to the Atlanta City Council's transportation committee.

McCrillis said the transit system was reviewing training procedures to determine whether changes are needed.

(Copyright 2006 by The Associated Press. All Rights Reserved.)