The police watchdog has launched an investigation after a Taser, baton and CS spray were used to detain a teenage girl.
A complaint was made to the Metropolitan Police about the level of force used when the 17-year-old was detained in Roman Road, East Ham.
The Met then referred the matter to the Independent Office of Police Conduct (IOPC), who are now calling on witnesses to the arrest to come forward.
The IOPC's interim regional director for London Sal Naseem said: "Having reviewed the complaint and viewed body worn video footage of the incident we decided that this matter requires an independent investigation.
"It is important for everyone involved that we understand the circumstances surrounding this incident.
"We will be speaking with the teenager and others who were with her at the time but we would ask that anyone else who may have information that would assist with our enquiries make contact with our investigators."
Anyone who saw the incident, which took place at around 7.20pm on Wednesday, May 8, is asked to email romanroad@policeconduct.gov.uk or call the incident room on 0800 029 4692.
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