Three people, including a police officer, have been stabbed at a train station in Manchester.
The Victoria station was forced to close following the incident on New Year's Eve, cancelling a number of tram services.
The trio are in a serious condition in hospital, and a man has been arrested.
BBC producer Sam Clack was at the scene said he heard a woman make "most blood-curdling scream", looked down at the platform and saw a man wielding a 12-inch (30cm) blade.
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"I just heard this most blood curdling scream and looked down the platform," Mr Clack said.
"What it looked like was a guy in his 60s with a woman of similar age and another guy all dressed in black.
"It looked like they were having a fight but she was screaming in this blood curdling way. I saw police in high-viz come towards him.
"He came towards me. I looked down and saw he had a kitchen knife with a black handle with a good, 12-inch blade.
"It was just fear, pure fear."
Police managed to subdue the attacker with pepper spray and a Taser.
British Transport Police said an officer was stabbed in the shoulder.
UK media reported the attacker shouted "Allah" as he carried out the stabbings.
New Year celebrations in the nearby city centre weren't affected.