A 17-year-old girl was sexually assaulted in three separate incidents in the space of an hour as she made her way home after a night out in East London.
On Friday 29 September, the teenager became separated from her friends in Bethnal Green and was trying to return to her home in central London.
Police have released CCTV footage which shows the young girl being carried along Cambridge Heath Road by the first suspect at 11.55pm.
The pair are then seen entering a doorway on the same road, close to where items of the girl's clothing were later found. Police say they were unable to provide a detailed description of the suspect except that he was wearing dark clothing.
Shortly after midnight, the girl is seen being followed by a second suspect, a bearded male on a racing bike, as she stumbled along Mint Street.
The man is seen wearing a baseball cap with a square/rectangular emblem front centre, a hooded zip jacket, which is two toned in colour, with the shoulders and upper back area being darker, exposing a plain tee-shirt underneath. He has dark trousers and a bag on his back.
The girl turns right into Three Colts Lane and heads in the direction of Bethnal Green Overground Station as the man continues to follow her before approaching her at Corfield Street.
He is then caught on camera directing the victim into a location back from the street. After a short period of time the attacker emerges and calmly walks away.
The girl emerges a few moments later, her clothing now looking dishevelled, as she continues to walk further down Corfield Street.
At around 12:45am, the victim was subjected to a third attack, which police believe may have involved two or three men.
The third suspect is caught on CCTV walking down Cornfield Street where he joins two other figures seen in the distance under some trees.
Police believe that the men sexually assaulted the teenager between some parked cars.
The third attacker then walks up Cornfield Street alone at 12:55am. Police said the man has a distinctive gait, which gives him the appearance of walking unevenly and is described as being slightly bow-legged.
Following her ordeal, a member of the public spotted the teenager lying on the ground in Cornfield Street and called 999 to alert police who arrived at the scene.
Police were called shortly afterwards and took her for examination and specialist support.
Officers from the Child Abuse and Sexual Offences Command (CASO) have already conducted public witness appeals and now are urgently seeking help from any members of the public who can identify either man in the footage or have any other information.
Toxicology tests have been carried following fears that the victim, who received specialist support, may been drugged.
Police investigating the attacks have appealed to the public for any information that may help reveal the identity of the perpetrators.
Detective Inspector Suzanne Jordan, from the Met's Child Abuse and Sexual Offences Command, (CAS0) said: "This is a horrific multiple sexual assault on an young female who was simply making her way home after a night out. We would like to thank the members of the public who intervened to help her and possibly prevented her ordeal from continuing even further.
"We believe two of the three were very serious sexual assaults indeed, and are determined to catch the persons responsible for these hideous crimes. I would urge anyone who recognises either male in these images to contact us as a matter of urgency.
"We'd also like to speak to any witnesses who haven't already come forward, or anyone with any information at all however insignificant they believe it might be - it could prove crucial to progressing our enquiries."
Anyone with information should contact the CASO team investigating via the Met on 101 or via twitter at @MetCC.
Information can also be provided anonymously by contacting Crimestoppers on 0800 555 111 or online at www.crimestoppers-uk.org