Glasgow trains face disruption after an 'emergency incident'.
ScotRail said they have had reports of a vehicle hitting a bridge at Dumbarton Central this afternoon.
The rail firm says the bridge is currently being examined by Network Rail staff.
Services are still able to pass over it, however, at a reduced speed.
A spokesperson for ScotRail said: "We've had reports of a vehicle striking a bridge at Dumbarton Central.
"The bridge is currently being examined by Network Rail staff, however services can pass over the bridge at reduced speed.
"Please keep an eye on your journey via our app, website or JourneyCheck."
A spokesperson for Network Rail added: "A vehicle has struck a bridge at Dumbarton Central.
"The bridge will need to be checked by specialist engineers although train services can still pass over the bridge albeit at a reduced speed.
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