Sweden is probably the best example of Muslim no go areas, but they are springing up all over Europe. I think Luton and parts of London are like this but not certain. Mere anectdotal evidence. But it is already a major problem.
What is to be done about it?
The simple fact is that there are too many Muslims preaching hate.
Why many want to refuse this fact is beyond me.
What I also find puzzling is that these same people who won't acknowledge this are the first to jump on anyone who does ... racist, Islamaphobe xeno ...zzzzzzzzzzzzzzzzzzzzzz
Just look at what they are taught. How they can ever call it a religion of peace when the passages in the Koran say the opposite. Our lily liveried politicians won't condemn it out of political correctness. Read Melanie Philips "Londonistan". Totally ignored by politicians.