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Illinois Senate Democrats advanced legislation late Wednesday to restrict semiautomatic weapons and high-capacity magazines, pressing forward with new gun control measures in the waning days of the session over the objections of firearms groups.

Amid the developments, the Illinois State Rifle Association issued an “urgent alert” to its members warning them that Democratic legislators were trying to push through last-minute anti-gun legislation.

“There would be no exemptions and no grandfathering,” the group stated in its alert. “You would have a very short window to turn in your guns to the state police and avoid prosecution.”

A Senate committee approved two bills, one dealing with the weapons and the other with magazines. Democratic supporters could face a tough sell in the full Senate.

One measure would ban the possession, delivery, sale and transfer of semiautomatic handguns and rifles. People who currently own such weapons could keep them but would have to register them. The bill would allow semiautomatic weapons to be used at shooting ranges, but those facilities would be regulated.

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National Rifle Association lobbyist Todd Vandermyde told lawmakers the bill would restrict about 75 percent of handguns and 50 percent of long guns in circulation today. He also said it would treat law-abiding gun owners like criminals, and is in conflict with Second Amendment rights upheld by the courts.

"I've never seen a piece of legislation that tramples on so many court decisions," Vandermyde said.

The other bill, introduced by Democratic state Sen. Dan Kotowski, would limit ammunition magazines to 10 or fewer rounds.

Those pushing for enhanced restrictions say stricter rules are needed in the wake of a string of high-profile mass shootings -- most recently the deadly school shooting in Newtown, Conn. Democratic Gov. Pat Quinn had been trying earlier this year to pass new legislation in the wake of the Colorado movie theater shooting, but lawmakers are taking another crack at it.

Kotowski sponsored legislation in 2007 that would have prohibited assault weapons and .50-caliber rifles. His bill made it through a Senate committee but died on the floor.

Another Democratic state lawmaker, Antonio Munoz, introduced the ban on all assault weapons “designed for war.”

Quinn has repeatedly tried to get stricter laws on the books but has fallen short.

The state Senate got back to work Wednesday. The House plans to return Monday. Both legislative bodies are working against a Jan. 9 deadline -- when the state’s new General Assembly will be sworn-in.

Gun manufactures in Illinois have already threatened to leave the area if laws limiting guns are put in place. ArmaLite owner Mark Westrom told FoxNews.com that he’s been fielding offers from at least two others states to move his operation if gun control laws in Illinois are pushed through.

The Associated Press contributed to this report.