The three boys, one aged 14 and two aged 16, were arrested on suspicion of assault occasioning grievous bodily harm (GBH). All three remain in custody at Thorpe Wood Police Station.
This comes following a police appeal after a boy, 13, from Hampton was seriously assaulted on October 31.
Police were called at 5.44pm to the assault in Hampton Hargate Hill by Hargate Way in Hampton.
The victim was walking with a friend when a group of youths threw an egg at him. The victim shouted back and the group of around 10 youths attacked him, causing serious injuries including a fractured eye socket and fractured jaw.
The victim was taken to Peterborough City Hospital and has since been discharged.
DS Tom Power said: “This was a violent attack which left a young boy seriously injured and needing hospital treatment.
“We are taking this incident very seriously and would like to reassure people that we are conducting neighbourhood patrols of the area.
“We believe there were a number of people in the area at the time of the assault and we strongly urge those people, or anyone with any information about the attack, to come forward.”
The investigation continues and anyone with any information is urged to contact the police via their web chat service or online forms quoting crime reference 35/74805/21.