A wheel fell off a commuter train, causing a derailment on the Fitchburg line Tuesday morning, confirmed Keolis.
The company, which operates the commuter rail system for the MBTA, said the problem derailed the train 404 car at approximately 07:45. None of the 800 passengers or train crew members were injured. .
Passengers were eventually transferred to other trains for their morning commute. A crane was used to redirect the car, which was taken to the Boston Engine Terminal for inspection.
"The vehicle in question and all associated components will be quarantined to allow detailed technical analysis," Keolis writes in a statement.
Keolis said that commuter rail cars, including wheels, are inspected daily.
"As a result of this incident and as a precaution, an inspection of all cars with the same equipment is underway and should be completed before the start of the evening drive," Keolis wrote. "In addition, the route on which this occurred has been inspected to ensure the safe passage of trains in this area."
Residual delays on the Fitchburg line are expected to be resolved before the evening commute, officials said.
"The safety of our customers and employees is our top priority," said Luis Manuel Ramírez, CEO of MBTA, in a statement provided by Keolis. "We appreciate the patience and cooperation of our passengers during this incident, and I would like to thank our teams for their efforts to restore the full service of Commuter Rail."