South West train services running into London Waterloo this morning may be subject to disruption, after an alarm was activated on an earlier train.
A communication alarm was activated on a train between Richmond and Mortlake, meaning there are delays on the route between Richmond and Waterloo, according to National Rail.
A passenger operated the emergency exit on a train at Richmond and all trains in the area were at a standstill whilst a safety check was made.
Trains are now on the move again but delays are expected to continue, due to congestion in the area.
Trains may be delayed by up to 20 minutes, the rail operator said, and the disruption is expected to continue until 11am.
The routes affected are between Reading / Shepperton / Farnham / Windsor & Eton Riverside and London Waterloo.
Earlier today, First Group announced it had won the South West trains franchise from Stagecoach, as part of a joint venture with with Hong Kong metro operator MTR.