POLICE were called to Abergavenny's rail station amid fears a man had been struck by a train over the weekend.
British Transport Police arrived to find a 30-year-old man was in the area of the track - but he had not been hit by a train.
But he had been trespassing on the railway - and for that he received a caution.
A BTP spokesman said the man was aged 30 and local to the town.
The alarm, raised at mid-afternoon on Sunday, resulted in a major response from the emergency services.
Abergavenny police commander Insp Huw Jones confirmed that initial reports suggested a man had been hit by a train. It was this 'fact' which dictated the level of the emergency service's response.
'It later appeared that no one had been struck by a train, and the matter was dealt with by BTP,' he explained.
Police and paramedics - including the Gwent Air Ambulance - rushed to the scene to answer the 999 shout, a rush of interest which puzzled town mayor Martin Hickman who witnessed the proceedings from his home near the station.
He said after the panic had died down, "I counted seven vehicles - three ambulances and four police vehicles, one of them unmarked. The police dog van was there."
The town's civic leader, who took the pictures, added, "The helicopter was moving almost sideways down the line. It landed in a field behind the Hereford Road. It was there for about half-an-hour before taking off."
He had also heard that someone may have been struck by a train, and expressed surprise that the matter was one of just trespass
"I wonder how much an incident like this must have cost," he said.
It's understood such incidents can usually hit the public purse to the tune of several thousand pounds, especially if the air ambulance is involved.
Arriva Trains Wales responded by cancelling services between the town and Abergavenny.
The interruption caused delays of an hour with normal services resuming at 5pm.
The BTP spokesman said, "Our officers attended shortly before 3pm and located a man near the railway line who was uninjured and had not been struck.
"The 30-year-old man from Abergavenny was arrested on suspicion of trespass at the scene and received a police caution."