Some Luas services cancelled after overhead cables damaged by vehicle
Some Red Line Luas services aren't running due to a technical fault.
There may be commuter chaos as there will be no service between the Red Cow/Tallaght and Saggart.
Independent.ie understands that the 750V overhead lines were damaged when they were struck by a vehicle.
Dublin Fire Brigade say the wires were left hanging.
The company said in a statement that bus services will be running.
They said: "Please be advised there is no service between Red Cow / Tallaght & Saggart due to a fault with the overhead cables at Belgard.
"Luas tickets are valid on Dublin Bus. Alternative bus service will be in place soon. We apologise for any inconvenience caused.
"All Green Line services are operating normally.
"All lifts and escalators are in full working order."