The teenagers battered the 14-year-old girl at around 3.30pm on Sunday April 4. Police are now trying to trace those responsible.
It is said two females in the gang of five led the assault while the others filmed it.
A relative of the girl told Devon Live the attackers stamped on the young girl’s head during the vicious assault.
Anyone with any information about the attack is urged to call police on 101 or via email at [email protected] quoting CR/026637/21.
Alternatively, potential witnesses can call the independent charity Crimestoppers anonymously on 0800 555111.