Registered gun owners in the United Kingdom are now subject to unannounced visits to their homes under new guidance that allows police to inspect firearms storage without a warrant.

The new policy from the British Home Office went into effect Oct. 15, permitting police and constabularies to conduct surprise home visits to legitimate gun owners.

“Americans should view the UK’s ever-expanding gun control efforts with grave concern,” the National Rifle Association’s lobbying arm said on its website Friday.

Britain’s gun owners were subject to the home visits before the update, but the inspection had to be conducted with prior notice.

“Where it is judged necessary, based on specific intelligence in light of a particular threat, or risk of harm, the police may undertake an unannounced home visit to check the security of a certificate holder’s firearms and shotguns,” the updated policy says.

In a letter to legal gun owners, a British police organization, the Association of Chief Police Officers, said the revamped guideline does not grant police any new powers but clarifies “the basis on which the visits should be conducted.”

ACPO is also encouraging tipsters to call a new Crimestoppers hotline to report any concerns they have about the storage of legal firearms.

The Home Office is apparently worried that legitimate guns could easily be stolen and wind up in the hands of terrorists.

But Shooting UK, a website for gun club members in Great Britain, said those worries may be overblown. The group said the Home Offices own figures show that theft of guns is not a widespread concern.

“On average, in the past five years, annually just 0.025 percent of the 1,837,243 legally held firearms and shotguns in England and Wales were stolen — an average of just 475 guns per year,” Shooting UK said. Those figures were not broken down to indicate how many firearms were stolen from a legal gun owner’s home.