Young people have reportedly been spotted "playing on railway tracks" on top of a bridge.
British Transport Police has been on patrol around the viaduct at Pill in North Somerset today (Thursday, April 15), after sightings of people on the tracks there.
The force's Avon and Somerset team shared a tweet just after 4pm, urging people to beware of the dangers.
It read: "Officers have been patrolling Pill Viaduct this afternoon after reports of youths playing on the railway tracks in the area.
"Please remember that not only is it illegal, it is extremely dangerous #stayoffthetracks."
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The viaduct stretches across Watchouse Road and Underbanks at its base, with the tracks carried across the top at quite some height above the road below.
British Transport Police shared several messages in the run-up to the Easter holidays following a rise in trespass incidents along railway tracks elsewhere.
In a statement specifically about the Barnsley area on March 31, officers warned it was just "a matter of time before someone is seriously hurt or worse".
Superintendent Alison Evans of British Transport Police said at the time: "Trespassing on the railway can have serious, life-changing consequences for the individual, their loved ones and the wider community.
"Please, make sure you know the rail safety basics and pass that knowledge onto your loved ones. Lead by example and stay off the tracks."
Sergeant Rob Pile added: "Parents and carers play a vital role in preventing tragedy resulting from trespass by ensuring they know where their children are and talking to them about the dangers of trespassing.
"So please, have that conversation with those in your care and encourage them to stay off the tracks."
