Police investigating a serious racist attack after apologising for failures in an earlier inquiry have been passed mobile phone video of the incident.
BBC Newsnight understands the footage shows two attackers, one of whom makes what seem to be monkey chants directed at three women in London.
The women said officers in the initial investigation made racist assumptions about them, hampering the inquiry.
The Metropolitan Police denies this, but said it is reviewing its work.
Last week Newsnight revealed serious failings in the police investigation into the attack on the three women, all of Somali descent, on 22 December last year.
Police closed the case in April, saying they had no CCTV evidence or leads.
But Newsnight found that officers failed to obtain CCTV from nearby shops or take witness statements, even from the victims, for nearly two weeks after the attack.
By the time the police tried to recover security camera footage from shops in Kilburn Lane in early January, it had been recycled - and overwritten by new material.
The Met reopened the case last week and apologised to the women. A source close to the investigation said the Met now has 21 lines of enquiry into the unsolved hate crime.
The former chief constable of Surrey Police, Bob Quick, told the programme the Met's response had been "woeful".
Niyad Farah, 38, was kicked unconscious in the attack and taken to St Mary's hospital, Paddington for treatment. It was categorised as racially motivated GBH with intent - a very serious hate crime.
Ms Farah told Newsnight that one officer asked her if she had been "buying anything" from the attackers. She believes he was implying they were buying drugs and knew the men.
She said she thought the officer believed "it was almost impossible for a racist attack to happen in that area".
The Met denies racist assumptions were made and says it accepted from a very early stage this was a vicious attack by strangers. But in response to Newsnight's investigation it apologised for failing the women.
In a statement, the Met admitted the incident "should have been escalated and prioritised at an earlier stage" adding "there was a delay in the necessary follow-up enquiries being made just after the incident, and this hindered the subsequent investigation".
"This shouldn't have happened, and we are sorry for letting the victims in this case down. This was an appalling attack which should have been investigated with greater urgency," the force said.
The Met has also referred itself to the Independent Office for Police Conduct.
It confirmed it has received new information relating to the attack.
Watch Newsnight's full investigation on iPlayer.