A woman was grabbed from behind and forced to the ground in Royal Mint Street at 6.40am on Saturday, 8 September.
The attacker then fled the scene after being noticed by a white van driverdwho reportedly saw the assault and chased the suspect.
“This is a horrific attack on a lone female,” said Detective Constable Safdar Mahmood. “Thankfully the timely appearance of the white van prevented further harm to the victim.”
Police have released CCTV footage and a picture of a suspect that they would like to trace.
They are also keen to speak with the driver of the van and anyone else who has any information that may assist the investigation.
The suspect is described as an Asian man, aged between 20 and 25 years, about 5ft 8ins tall and of stocky build.
Anyone with information should contact Detective Constable Safdar Mahmood via 101 or call Crimestoppers anonymously on 0800 555 111 or visit crimestoppers-uk.org.
Tags: Tower Hamlets