On Saturday, June 16, 2018 at 7:46:46 AM UTC+1, MrCheerful wrote:
The thief was riding a bike and was described as black, about
25-years-old, slim, with short hair, and wore dark clothing and blue
trainers

https://www.bristolpost.co.uk/news/b...chains-1681097

"Between 3pm and 3.30pm a 36-year-old woman had her gold necklace taken as she was standing on Somerset Terrace, Redcliffe, with her children. The thief approached her from behind and ran off."

So one of the thieves was a pedestrian, you forget to mention that.