Several people were injured and nine were taken to hospital, including one with leg injuries, after panic erupted in the crowded station on Friday.
Police were called at 16:38hrs on Friday, 24 November to a number of reports of shots fired on Oxford Street and underground at Oxford Circus tube station.
The British Transport Police said it believed there had been an altercation between two men on the platform before the scare.
"We appealed for information following an incident at Oxford Circus yesterday".
'At this stage, we are examining the circumstances of the incident which resulted in the station being evacuated.' 'During the station evacuation, one woman is believed to have sustained a minor injury.
The post immediately sparked outrage on social media after police revealed there was no evidence of shots being fired or casualties.
Officers sealed off the surrounding area and closed Bond Street station as a crowd control measure while armed police responded to the reports.
Police initially treated the incident as potentially terror related, but officers stood down after finding no evidence of shots being fired. "Armed and unarmed officers are on scene and dealing along with colleagues from British Transit Police", the force tweeted.
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Selfridges later said the evacuation of its shop was a precautionary measure and there were "no reported incidents in store".
Included in the piece, it read: "There is a lorry stopped on the pavement in Oxford Street, police all around it and blood on the floor, it's definitely the aftermath of something maybe just a crash but nothing on the news..."
"She said there had been a stampede because something had happened".
'Someone said it was a shooting - and people were running away and into buildings.
"We were in the Kingdom of candies and then saw a massive crowd of people running and screaming".
In a statement, Mayor of London Sadiq Khan praised the city's emergency services for a "swift response". One witness on Twitter said there had been "a fight on the westbound platform that involved around 20 people".
Anyone with any information can call BTP on 0800 40 50 40 or text 61016 citing reference 405 of 24/11.More news: Salvation Army serves hot meals to those in need