Yep,
Britain interned citizens of Italian, German or Austrian extraction in the war's early years, until their allegiances could be ascertained. Those not considered a threat were released, and some joined the forces. Those considered a threat were usually shipped off to camps in one of the Commonwealth countries-Canada, Australia, New Zealand etc.
In the early part of the war, a U-Boat torpedoed a merchant ship (the Arandora Star?) carrying German & Italian internees to Canada. Many were killed.
After the Italian armistice, all Italians were released, and internment had more or less ceased by that point for practical reasons anyway.
Best (only!) book I've come across on it was
Collar the Lot! How Britain detained and Expelled its wartime Internees. Forget the authors' names though-Leni & Peter Gilman?
A couple of years back, English Heritage published a survey into POW camps in Britain in WW2,and this also included internment camps.
You can read it here:
POW and Internment Camps in Britain 1939-1948
