The Canadian government has banned 1,500 assault-style weapons effective immediately.

Prime Minister Justin Trudeau made the announcement on Friday, noting it is now illegal to buy, sell, transport, import, or use “military-grade assault weapons” in Canada.

“These weapons were designed for one purpose and one purpose only: to kill the largest number of people in the shortest amount of time,” Trudeau said.

He listed a number of mass shootings in Canada, including the recent Nova Scotia rampage that left 22 people dead.

Trudeau said there is a two-year amnesty period for owners of banned weapons and that a buyback program will be legislated. Gun owners will be able to export the prohibited weapons if they have an appropriate permit.

Gun owners shouldn’t attempt to surrender newly banned guns to police during this COVID-19-related physical distancing period, he added.

Public Safety Minister Bill Blair addressed law-abiding Canadian gun owners, saying that the new regulations won’t interfere with “lawful” activity.

While he said assault-style weapons may have some recreational value, “these powerful weapons become deadly weapons when they fall into the right hands.”

Blair said the government also plans to introduce “red-flag laws” to make it easier for law enforcement to confiscate guns from people who are suicidal, involved in domestic violence, or “advocating hate” against religious minorities and women.

The term “assault weapon” is contentious in the firearms community, with many gun proponents arguing that it’s meaningless without being clearly defined. Gun expert A.J. Somerset told VICE the best definition is a semi-automatic centrefire rifle with an attachable magazine and a pistol grip.

Somerset said the new policy could leave loopholes because the government isn’t banning a whole category of guns with certain characteristics, but rather going after specific makes and models. That means that some guns that have similar characteristics to the banned weapons may remain on the market.

Trudeau said he also plans on allowing municipalities to ban handguns.

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