Metro said it is sidelining 94 of its Orion VI diesel buses after two caught fire in the past week. No one was injured in either incident.

One incident occurred last Thursday about 8 p.m. as a bus was headed westbound on Interstate 66 near Nutley Street. The fire originated in the rear of the bus, according to Metro spokesman Dan Stessel.

He said the driver of the bus escaped without injury and there were no passengers aboard the buses.

A second fire happened Tuesday morning on a bus on Route 50. There were no passengers aboard that bus, either. A mechanic, who was driving the bus at the time, did not suffer any injuries.

“Given the fact we’ve had two fires involving these buses in the span of a week, it is a prudent step to take while we investigate the underlying cause and determine next steps,” Stessel said.

In a news release, Metro said: “The buses will remain out of service until further notice.”

The buses are a small part of Metro’s fleet of 1,492 buses.

Metro said it bought the Orion VI buses starting in 2000.

Since the two fires, Metro said it has hired an “outside fire protection engineer” to help its safety department investigate the incidents.

Stessel said other buses that are usually in reserve will be used to replace the 94 buses that run on routes in Prince George’s, Fairfax and Arlington counties, Northeast Washington, Alexandria and Garrett Park.

“Customers should see little to no impact,” he said.

The latest service problems come after Metro said it is repairing 47 of its new hybrid buses because they can develop shorts in their battery systems.

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