According to Firearm Chronicles
When someone is deported by a nation, it means they’re not welcome there anymore. It usually takes something egregious to warrant deportation, though. Most nations don’t deport people because there’s eyes are blue or because they support gun control, though we should rethink that last one. No, they usually do it because they believe the person tends to represent a threat to their nation in some way.
That doesn’t mean the deported individual stays deported, though.
More importantly, when that individual is a criminal, don’t be surprised if they come back with illegal firearms.
A Palmers Green man who managed to sneak back into the UK after being deported to Albania five years ago has been caught with two loaded guns and £70,000 worth of cannabis.