Articles like this [1] (re: Rochdale gang) are contributing to the impression of a link in the UK. There's also the Rotherham child sexual exploitation scandal [2] which affected an estimated 1,400 girls specifically in Rotherham. Population of Rotherham is 265,800, for reference. In both these cases, girls were charged and the offenders are Pakistani.
There is also a recent video of a girl wielding an ax and knife to protect her and her sister in Scotland [3]. She has been charged with brandishing weapons. Interestingly, the BBC has issued an article [4] claiming that it was a "Bulgarian couple" that the girls approached, and to not "spread misinformation." I am a researcher of Slavic languages, so I can tell you from watching the video in [3] that the accents featured in this video are not Bulgarian. I am not willing to stake a claim in what they actually are (someone else is welcome to comment).
Actually, I'm quite alarmed that the BBC is claiming this, as I generally consider the BBC reputable.
I just overlaid that with the immigration into uk with that chart (both from statista) - charts are disturbingly similar trend. I would hope that its correlation and not causation but its definitely eye opening and kind of concerning.