其中一人用 "帶刃物品 "威脅她，另一名嫌疑人據說襲擊了她，造成面部受傷，然後她的自行車被盜。
Det Insp Owen Fell說。"我們想向當地社區保證，我們已經開始針對這些事件進行全面調查。
The victims have had a bike, bag and an e-scooter stolen from them after being approached by groups of males, detectives said.
The force appealed for anyone with information "no matter how small it may seem" to come forward.
One threatened her with a "bladed article" before another suspect is reported to have assaulted her, causing facial injuries, before her bike was stolen.
The second took place between 17:00 BST and 18:00 BST on 24 June at Jubilee Park on Greenmoor Road where a teenage girl had her bag stolen.
On Sunday, a woman in her 40s was riding an e-scooter on Orkney Close when she was approached by a group of around 10 teenage boys.
One is understood to have pushed her from behind causing her to fall and fracture her elbow.
At 20:30 on Monday, a teenage girl was playing football at Jubilee Sports Centre, also on Greenmoor Road, when she was approached by a group of five males and one female.
Det Insp Owen Fell said: "We would like to reassure the local community that we have begun a comprehensive investigation in response to these incidents.
"We're pursuing a number of lines of enquiry as part of our ongoing investigation, but we'd also appeal for anyone who witnessed any of the incidents to come forward."