Metropolitan police tweeted at 11:44pm tonight that officers were on the scene.
At around 12:30am, Scotland Yard confirmed the incident was not connected to the activity in London Bridge, which was confirmed as being terror-related.
Police are responding to a third incident following chaos on London Bridge
Armed police rushed to the popular Borough Market after a car mounted the pavement on the popular bridge.
Dramatic footage from the area, which is popular with diners and tourists, shows police running into a bar, instructing panicked revellers to “get down”.
Police set up a cordon after the incident
Eyewitnesses report seeing men running down the street with large knives, stabbing revellers at random.
A taxi driver called Chris told LBC he saw men armed with foot-long knives after a van drove on to the pavement.
He told the station: "I didn't see the van mount the kerb, but I saw everything else.
"A van came from London Bridge itself, went between the traffic light system and rammed it towards the steps. It knocked loads of people down.
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Revellers fled the scene near Borough Market
"Then three men got out with long blades, 12 inches long and went randomly along Borough High Street stabbing people at random.
“I saw a young girl stabbed in the chest.”