Residents rushed to the aid of a teenage boy who had been stabbed in the buttocks on Monday.

Police were called to a street in Custom House at around 4.15pm where they found members of the public tending to a 17-year-old lying on the ground with a stab wound to his lower right buttock.

The young man said he was chased from a nearby park by a group of 10 to 15 youths who caught up with him in Varley Road where he was stabbed and his mobile phone taken.

He also suffered bruising above his left eye and grazing to the right side of his head.

Officers set up a crime scene and administered first aid to the victim until an ambulance arrived to take him to an east London hospital.

A doctor described his injuries as non-life-threatening or changing and the teen discharged himself from the hospital.

Police arrested a 16-year-old male for grievous bodily harm at 7.45pm that day and he remains in custody at an east London police station while officers continue their investigation.