(CBS) — An Illinois Senate Committee has approved a measure that would limit the size of ammunition clips sold in the state.

By a vote of 12-3 Monday, the Senate Executive Committee banned the future sale and purchase of so-called high capacity ammunition clips – magazines that hold more than 10 rounds.

The vote came after two Newtown, Conn. parents of grade-schoolers killed by gunman Adam Lanza appealed to Illinois lawmakers for their support. They argued Lanza’s use of high-capacity magazines helped him kill 20 children and six adults with efficiency late last year at Sandy Hook School; Lanza took his own life as police closed in.

Legislators observed a moment of silence for the parents’ slain children.

“I walked him to the bus, hugged him told him I loved him. That was the last time I saw him,” parent Mark Barden said of his 7-year-old son, Daniel.

Proponents of the legislation had brought the parents first to Chicago, on Sunday, and then to Springfield to describe the chaos in Newtown that morning.

“Today, we took the first step towards banning the sale of high-capacity ammunition magazines in Illinois, which will make our communities safer,” Gov. Pat Quinn said in a written statement. “By adopting Senate Bill 1002, Illinois would join 10 other states across the country that put reasonable restrictions on the size of these weapons.”

As the still-grieving Newtown parents were testifying in Springfield, Chicago Police Supt. Garry McCarthy was describing the seizure of another extended magazine assault weapon in Chicago.

“Now, tell me why anyone would need such a weapon on the streets of Chicago,” he told reporters.

The National Rifle Association was among the opponents of the bill, which now goes to the full Senate.

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