In the UK, anyone from SW Asia or even looks like they were (Even if they come from North Africa or Turkey) will be referred to as 'Asian,' while people we'd call Asians might be called 'Oriental' or some other neutral word.
If they make a point of referring to someone as 'British citizen,' it generally means they aren't White native-born Brits, because if they were, they wouldn't even mention it at all. It won't necessarily mean they are Muslims, as they use this odd bit of doublespeak for people whose citizenship status directly or indirectly resulted from minorities who moved there under the Empire or its legal immigration legacy from places like India, Pakistan, Nigeria, Kenya, India, South Africa, Jamaica, and so on...but very few of any of them are involved in violent crimes in England except the Muslims (Crime is no stranger to the non-Muslim Nigerians or the Jamaicans, of course, but they're in it for money, not ideology, so it's never in the nature of a killing spree or bombing).