A Metropolitan Police Community Support Officer has been stabbed while on duty in central London.
The suspect fled the scene chased by a police officer
The man, thought to be in his 30s, was attacked near Lloyds Bank in Victoria Street at 1000 BST.
A Metropolitan Police spokeswoman said the officer had been treated in hospital for minor injuries and had since been discharged.
Police have confirmed that a man in his 30s has been arrested in connection with the stabbing.
Victoria Street was cordoned off while police with sniffer dogs carried out a search of the area.
A large public square in front of Westminster Cathedral was also cordoned off and up to eight police vehicles, including two recovery lorries, were called to the scene.
The spokeswoman said: "At approximately 9.56am in Victoria Street outside Lloyds Bank, a male Police Community Support Officer was stabbed.
"London Ambulance Service attended. He has been taken to a central London hospital suffering from what are believed to be non life-threatening injuries."
'Punching the driver'
Tracey Harmer, who saw the attack, said she saw a man in his 20s walking in the middle of the road following a police van.
"The van was stationary in traffic and he caught up with the driver's side window.
"He put his arm up and the next minute he looked like he was punching the driver."
She said the man then ran off towards the cathedral with an officer in pursuit.