Investigators have arrested 13-year-old boy after sex attacks from nine women.
Women were subjected to unwanted sexual contact in East London during a five-week period, said Metropolitan Police.
All attacks took place between 6 September and 11 October.
Scotland Yard said the incidents were grouped around the Blackwall Way, Poplar, and it took place in the evening.
A 13-year-old boy was arrested by investigators involved in the attacks.
It was held in November.
The spokesman for the force said, "In the E14 area, sexual assault investigators arrested him.
"A 13-year-old boy was arrested on Thursday, November 1, after attending an East London police station.
"Since then it has been on the November date until further investigation.
"Arrest was followed by information after nine women were sexually assaulted over a period of five weeks in the E14 area, particularly around Blackwall Way.
"Sexual contact attacks occurred on Thursday, September 6 and Thursday, October 11, and they were all between 18.30 and 20.4."
The police stepped up the patrols in the neighborhood to reassure the population.
They are urging anyone to go alone, especially women, to stay vigilant.