There are delays of up to 15 minutes on train services in the Portsmouth area this morning after a vehicle struck a bridge.
Network Rail said it had received reports of the incident between Fareham and Cosham, and had sent engineers to inspect the site.
Trains are having to run to reduced speeds of 20mph around the area while the inspection is taking place.
Disruption is expected to last until at least midday.
For more information use the hashtag #Fareham on Twitter or visit the National Rail website.