Police are seeking a motorcyclist and the driver of a coach bus, both of whom fled the scene after a six-vehicle chain-reaction crash last week in Holtsville that left a 53-year-old woman seriously injured.

The crash occurred on Nicolls Road, near the Long Island Expressway, at 9:58 p.m. Sept. 11. Suffolk County police said the motorcyclist was in a group of motorcyclists and collided with the bus. Also involved in the crash were a 2010 Toyota, a 2004 BMW and a 2003 Pontiac.

The driver of the BMW, a woman from Farmingville, was transported to Stony Brook University Hospital -- and is in serious condition.

Police said the bus driver "pulled over" a short distance from the crash scene, but then left without reporting the accident to police. The motorcyclist fled, police said.

Police are asking anyone with information about the crash to call Crime Stoppers at 800-220-TIPS. All calls will remain confidential.

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