MARTA is investigating after a freight train slammed into a bus near downtown Decatur before daybreak Wednesday. There were no injuries, thanks in part to a quick-acting bus driver.

A bus on Route 123 was hit by the train about 6:30 a.m. at the McDonough Street crossing near East College Avenue, just south of Decatur High School.

Bus driver Donna McMullen said the northbound bus became “stuck” as it proceeded across the tracks, MARTA spokesman Lyle Harris said. McMullen followed emergency protocol and safely evacuated the four passengers from the bus before it was hit by the westbound train, he said.

The seriously damaged bus came to rest off the roadway, wedged between the train’s engine and the crossing arms, which were toppled in the collision. It was later towed away.

McMullen, 61, took a mandatory drug and alcohol test after the accident and was placed on leave with pay, pending the outcome of the investigation, Harris said. She has worked for MARTA since 1994.

The bus involved in the incident had no known mechanical problems, Harris said.