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Maryland's ban on 45 kinds of assault weapons and its 10-round limit on gun magazines were upheld Tuesday by a federal appeals court in a decision that met with a strongly worded dissent.

In a 10-4 ruling, the 4th U.S. Circuit Court of Appeals in Richmond, Va., said the guns banned under Maryland's law aren't protected by the Second Amendment.

"Put simply, we have no power to extend Second Amendment protections to weapons of war," Judge Robert King wrote for the court, adding that the Supreme Court's decision in District of Columbia v. Heller explicitly excluded such coverage.

Maryland Attorney General Brian Frosh, who led the push for the law in 2013 as a state senator, said it's "unthinkable that these weapons of war, weapons that caused the carnage in Newtown and in other communities across the country, would be protected by the Second Amendment."

"It's a very strong opinion, and it has national significance, both because it's en-banc and for the strength of its decision," Frosh said, noting that all of the court's judges participated.

Judge William Traxler issued a dissent. By concluding the Second Amendment doesn't even apply, Traxler wrote, the majority "has gone to greater lengths than any other court to eviscerate the constitutionally guaranteed right to keep and bear arms." He also wrote that the court did not apply a strict enough review on the constitutionality of the law.

"For a law-abiding citizen who, for whatever reason, chooses to protect his home with a semi-automatic rifle instead of a semi-automatic handgun, Maryland's law clearly imposes a significant burden on the exercise of the right to arm oneself at home, and it should at least be subject to strict scrutiny review before it is allowed to stand," Traxler wrote.

National Rifle Association spokeswoman Jennifer Baker said, "It is absurd to hold that the most popular rifle in America is not a protected `arm' under the Second Amendment." She added that the majority opinion "clearly ignores the Supreme Court's guidance from District of Columbia v. Heller that the Second Amendment protects arms that are `in common use at the time for lawful purposes like self-defense."'

The NRA estimates there are 5 million to 10 million AR-15s -- one of the weapons banned under Maryland's law -- in circulation in the United States for lawful purposes. Asked about an appeal, Baker said the NRA is exploring all options.

But Elizabeth Banach, executive director of Marylanders to Prevent Gun Violence, said the decision is "overwhelming proof that reasonable measures to prevent gun violence are constitutional."

"Maryland's law needs to become a national model of evidence-based policies that will reduce gun violence," Banach wrote in a statement.

U.S. District Judge Catherine Blake upheld the ban in 2015, but a divided three-judge panel of the 4th U.S. Circuit Court of Appeals ruled last year that she didn't apply the proper legal standard. The panel sent the case back to Blake and ordered her to apply "strict scrutiny," a more rigorous test of a law's constitutionality. The state appealed to the full appeals court.

Maryland passed the sweeping gun-control measure after the 2012 Sandy Hook Elementary School massacre that killed 20 children and six educators in Connecticut. King mentioned the massacre at the start of the ruling.

"Both before and after Newtown, similar military-style rifles and detachable magazines have been used to perpetrate mass shootings in places whose names have become synonymous with the slaughters that occurred there," King wrote. He listed the 2012 shootings at a movie theater in Aurora, Colorado; the December 2015 shootings in San Bernardino, California; and the shootings last year at an Orlando, Florida, nightclub, where 49 people were killed and 53 injured.

King also noted that enacting the law is "precisely the type of judgment that legislatures are allowed to make without second-guessing by a court."

"Simply put, the State has shown all that is required: a reasonable, if not perfect, fit between the (Firearms Safety Act) and Maryland's interest in protecting public safety," King wrote.