A councillor is urging the public to come forward with information after a 13 year-old was sexually assaulted at the weekend.
The teenager was attacked twice on Sunday by a group of youths in a block of flats in Essex Road and then again in Stoneydown Park in Walthamstow.
Police and detectives from the Sexual Offences Exploitation and Child Abuse Command are investigating the assault, which happened between 5pm and 9pm.
High Street ward councillor and cabinet member for economic growth and high streets, Clare Coghill said: "I am completely devastated about this assault on a child in our community.
"It's appalling that people are capable of such acts. I appeal to anyone with any information to come forward as soon as possible in order that justice can be served and the perpetrators punished."
Police cordoned off the park from around 7am on Monday and officers remained at the scene late into the evening.
Flora Fyfe-Graham, 37, of Newport Road, is a governor at Stoneydown Park Primary School and regularly interacts with teenagers at the park.
She said: "The park is generally not unsafe and is a really vibrant place for children and the local community.
"I don't think the park should be tarnished by this horrible, terrible, act of crime but I do think parks could be made to feel safer.
"I've had lots of interaction with teenagers in the park and although they may be intimidating, I've had many positive experiences and they've always been polite and accomodating.
"It is only natural to worry and we can all contribute to making the park safer including making the council work harder to invest in park safety."
Entrances to the park remained closed and taped off. No arrests have been made and enquiries continue.
Police are urgently appealing for anyone with information to contact the incident room on 0208 217 6541 or call Crimestoppers anonymously on 0800 555 111.