Two teenage boys were robbed and assaulted by two masked men at Wrecclesham recreation ground last Thursday evening.
The mum of one of the teens said they were “just sitting talking” at the rec when they were “jumped by two blokes with balaclavas” and punched “a couple of times”.
The thieves stole a bike, rucksack and iPad.
It happened at around 7.30pm. Surrey Police have been made aware and urge witnesses to call 101.
A police spokesman said: "I can confirm that we received a report of a robbery of two teenage boys at Wrecclesham recreation ground on Thursday, December 7.
"The investigation into this is ongoing."