New York state enacted the nation's toughest gun restrictions Tuesday and the first since the Connecticut school massacre, including an expanded assault-weapon ban and background checks for buying ammunition.

Democratic Gov. Andrew Cuomo signed the measure into law less than an hour after it won final passage in the legislature, with supporters hailing it as a model for the nation and gun-rights activists condemning it as a knee-jerk piece of legislation that won't make anyone safer and is too extreme to win support in the rest of the country.

"Common sense can win," Cuomo said. "You can overpower the extremists with intelligence and with reason and with common sense."

Owners of an estimated one million previously legal semi-automatic rifles, such as the Bushmaster model used to kill 20 children and six adults in Newtown, Conn., a month ago, will be allowed to keep their weapons but will have a year to register them with police. The sale of any more such weapons is prohibited.

"When there's a pileup of events, when the federal government does not do it, the state of New York has to lead the way," said state Assemblyman Joseph Lentol, a Brooklyn Democrat and co-sponsor.

Background checks for ammo buyers

In addition to outlawing a broader array of military-style weapons, the measure restricts ammunition magazines to seven rounds, down from the current 10, creates a more comprehensive database of people barred from owning guns, and makes New York the first state to require background checks to buy bullets. The system will also help flag customers who buy large amounts of ammo.

Jimmy Greene and Nelba Marquez-Greene, parents of Sandy Hook School shooting victim Ana Marquez-Greene, react during a news in Newtown, Conn., on Jan. 14. The parents joined a grassroots initiative called Sandy Hook Promise to support solutions for a safer community. (Jessica Hill/Associated Press )

In another provision, therapists, doctors and other mental health professionals will be required to tell state authorities if a patient threatens to use a gun illegally. The patient's weapon could then be taken away.

Richard Aborn, president of the Citizens Crime Commission of New York City, said Cuomo clearly understood gun violence is a complex issue requiring broader solutions than simply banning a particular weapon. "I think that's an important message for the nation," he said.

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In a statement, the National Rifle Association said: "These gun control schemes have failed in the past and will have no impact on public safety and crime."

"While lawmakers could have taken a step toward strengthening mental health reporting and focusing on criminals, they opted for trampling the rights of law-abiding gun owners in New York, and they did it under a veil of secrecy in the dark of night," the NRA said.

Obama could take steps through executive action

President Barack Obama will unveil his own proposals in response to the Newtown tragedy on Wednesday. He favors sweeping gun legislation, including a ban on assault weapons. But because of powerful opposition from the gun lobby, he is said to be weighing 19 steps he could take through executive action alone.

Those could include ordering stricter action against people who lie on gun-sale background checks, seeking to ensure more complete records in the federal database, and striking limits on federal research into gun use.

New York's law passed the state Senate, which is run by a Republican-dominated coalition, 43-18 Monday night. The Democrat-controlled assembly approved it 104-43 Tuesday afternoon.

Republicans complained the measure was rammed through the legislature and infringes on the Second Amendment right to bear arms.

"A lot of people say, `Why do you need these guns?"' said Assemblyman James Tedisco, a Schenectady Republican. "It's part of the freedoms and liberties we have.… It's for our public safety. It's to protect us from our own government."

He said the bill was dangerous because it would give people a "false sense of well-being."

"You are using innocent children killed by a madman for your own political agenda," he said. "You are actually making people less safe."

Legal challenge expected

Tom King, president of the New York State Rifle & Pistol Association, questioned whether other states or the federal government would follow New York's lead and said he expects the law to be challenged in court.

Previously, New York state law on assault weapons banned semi-automatics that have detachable magazines and at least two military-type features, such as a pistol grip, folding stock, muzzle flash suppressor or bayonet mount. The new law outlaws weapons with just one of those features.

It also requires background checks for even private gun sales, except those among immediate family.

In addition, it says handgun owners must renew their licenses every five years, and it increases prison sentences for using guns in various crimes or taking them onto school grounds.

"By making this a priority, the governor has not only saved lives but will hopefully inspire leaders in Washington also to take swift action," said Dan Gross, president of the national Brady Campaign to Prevent Gun Violence.

In a concession to the pro-gun side, local authorities will be allowed to withhold the identities of registered gun owners — an issue that erupted recently when a suburban New York City newspaper published the names and addresses of gun owners in its readership area.

The New York legislation sparked spirited discussion among customers at the Buffalo Gun Center in the suburb of Cheektowaga, where business was so brisk that people had to wait in line in freezing temperatures just to get in the door.

"It's ridiculous. It's absolutely — how to put it nicely — it's Prince Andrew Cuomo's bid for the White House," said Jim Hanley, who was waiting to buy another handgun. "I want to do it before the right is taken away. Andrew Cuomo and Barack Hussein Obama are two best gun salesmen in the history of the world."