DCI Adam Lowe said:
"These arrests are part of an investigation into rape and serious sexual assault carried out by a group of men in Newham and the wider east London area. Our enquiries continue.
"I would urge anyone who has been a victim of this type of offence or who believes they have any information to please contact police on 020 8217 6531, or Crimestoppers on 0800 555 111."
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