Police have been called to Hatfield Station to persude a woman to get off the railway tracks.
British Transport Police were called at 1.15pm out of concern for her welfare.
According to one eyewitness, the woman was attempting to walk in the direction of King’s Cross.
A helicopter, police cars and several police have been spotted at the scene.
“Commuters are all waiting on the platform, it’s a hostile environment,” said another anonymous passer-by who had been waiting for a bus outside the station.
“Everyone seems really angry.”
He said that the situation had unfolded for about 25 minutes.
A statement on Great Northern’s website said that the trespasser had caused all trains in the area to be at a standstill “in the interest of safety”.
“Network Rail response staff and the British Transport Police are on site attending to this incident, working to escort the individual away from the railway and to a place of safety.”
British Transport Police said no arrests had been made and that the woman, who is in her thirties, was taken to a place of safety.
Trains are now running as normal.
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