Two people have been injured and one is missing after a church collapsed near a railway line in Cardiff.
Firefighters, rescue dogs and a drone are searching for a casualty in the wreckage of the derelict church in Splott, which collapsed at about 14:50 BST.
Two people escaped from the building – which was being demolished – and were treated for minor injures.
Limited trains are running between the capital and Newport.
Network Rail warned commuters rail services across the network could be affected following the incident.
Cardiff demolition firm Young Contractors, who have been working on the derelict church for about three weeks, confirmed none of its staff were on the site at the time.
Eric Bellew, of South Wales Fire and Rescue, said an extensive search using specialist rescue teams, dogs and a drone was under way.
He said: “Two people self-rescued at the incident with minor injuries and we are in the process of searching for a further individual.”
A warning was sent to a train heading towards the scene, but the driver did not report anything “untoward” on the line, Network Rail said.
However, South Wales Police has since confirmed scaffolding was on the tracks.
Officers have taped off part of Pearl Street close to the derelict church.
All trains were initially cancelled between Cardiff and Newport, but two lines have now reopened, with disruptions expected until about 17:30.
A Network Rail spokesman said: “We are working with our partners, Arriva Trains Wales, Great Western Railway and Cross Country, to update passengers as and when more information becomes available.”
Cardiff South MP Stephen Doughty tweeted: “Very concerned to hear reports of derelict church collapse by #Splott Road – am in contact with @networkrail @swpolice @SWFireandRescue”.
The Evac emergency alert phone app – which provides information about major incidents, fires, floods and terrorist attacks – warned users all main train lines between the capital and Newport were closed.
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