CHICAGO – As news spread of the U.S. Supreme Court’s decision Thursday to strike down Washington D.C.’s handgun ban, one thing was clear in Chicago: The city’s own ban now faces a challenge as serious as any in its 26-year history.

From a visibly angry Mayor Richard Daley to a federal lawsuit filed within hours that challenges the Chicago’s ban as unconstitutional, there was no mistaking that the high court’s 64-page opinion puts the city’s law squarely in the middle of a long legal battle.

While swift, the lawsuit certainly wasn’t a surprise given that Justice Stephen Breyer, in his dissenting opinion, noted “Chicago has a law very similar to the District’s.”

“In the sense the Supreme Court has found this is an individual right to bear arms, we recognize (the ruling) is a significant threat,” said Jennifer Hoyle, spokeswoman for the city’s law department. “It gives people an opening to challenge the ordinance in a way it hasn’t been challenged in many years.”

Hoyle said the high court’s decision does not invalidate Chicago’s law and attorneys are confident they can successfully fight off any legal challenge to the 1982 ordinance that makes it illegal to possess or sell handguns in the city.

“We have very strong legal arguments to make at every level of the courts,” pointing out, for example, that the gun law constitutes a reasonable restriction for a densely populated urban area.

But Hoyle fully expected legal challenges.

In fact, even as Richard Pearson, executive director of the Illinois State Rifle Association, was saying his organization may give Chicago and other Illinois municipalities some time to change their laws, his group and others were filing a lawsuit against the city and Daley.

“By banning handguns, Defendants currently maintain and actively enforce a set of laws, customs, practices, and policies under color of state law which deprives individuals … of their right to keep and bear arms,” read the lawsuit filed by the ISRA, the Second Amendment Foundation and four individuals.

The quick action is welcome news to gun enthusiasts, who say laws like Chicago’s have chipped away at their rights.

“The justices just ruled today to uphold the Constitution,” said Deb Gales, who owns Deb’s Gun Range in Hammond, Ind., just across the state line from Chicago. “We all know that these anti-gun laws have been passed to the detriment of law-abiding citizens.”

But all the talk of rights and legal challenges doesn’t begin to explain what this ruling means at this moment in time in Chicago – a city shaken by gun violence for months.

Last spring saw a 16-year-old high school student shot and killed, and four fellow students injured, when someone sprayed bullets inside a bus they rode in the middle of the day. This spring saw a weekend during which nine people were killed in 36 shootings. The next week, five people were found shot to death inside a pillaged South Side home.

Chicago Public Schools officials say 27 students have been killed by gunfire since September. And just this week an 8-year-old boy was shot and seriously injured while riding in a van, a victim, police said, of his parents’ gang and drug involvement.

“If hunters want to hunt, that’s fine,” schools CEO Arne Duncan said Thursday. “It’s when adults hunt children, that’s the problem.”

Pamela Bosley lost her 18-year-old son two years ago, when a bullet from a handgun hit him as he helped a fellow student unload instruments outside a South Side Church.

“If you didn’t have the guns, we’d still have our children,” she said.

Annette Nance-Holt, the mother of 16-year-old Blair Holt, who was killed on the city bus last May, was livid Thursday.

“I’m still trying to figure out who we are more in love with, our children our guns,” she said. “It’s crazy. I’m safer being a deer knowing people are hunting you.”

Daley was equally troubled by the ruling.

“It’s a very frightening decision,” said the longtime gun control proponent who routinely speaks out against guns, as he did after the fatal mass shootings at Northern Illinois University and a suburban women’s clothing store. “We believe every mayor will be outraged by this.”

The mayor criticized justices he said make decisions from behind the safe walls of a courthouse that put people outside those walls at risk.

“If you’re an elected official, you feel safe. You cannot carry a gun into a federal building. You cannot carry a gun into a federal court,” Daley said. “So, they’re setting themselves aside.”

Nance-Holt agreed.

“They live in safe neighborhoods,” she said. They don’t have this. Until it’s their family member, they’re going to keep voting that way.”

Associated Press writers Michael Tarm, Ashley M. Heher, Jenny Song and Carla K. Johnson contributed to this report from Chicago and Daniel J. Yovich contributed from Hammond, Ind.