Maryland Governor Martin O'Malley introduced tight new gun control laws Thursday, which are some of the toughest in the United States.
The legislation, prompted by the Sandy Hook massacre in which 26 children and teachers were gunned down, includes banning the sale of 45 assault-style rifles, the Baltimore Sun reported.
The Democrat has also limited gun ownership for people with mental illness, and banned the sale of high-capacity magazines.
O'Malley said such measures "will substantially lower gun deaths."
The legislation requires police to fingerprint new owners of handguns before they are granted a license, Reuters reported.
"We've chosen to take action by advancing the strategies that work to save lives," O'Malley, who has been mentioned as a potential presidential candidate in 2016, said in a statement.
The National Rifle Association has already indicated it plans to challenge the new laws in court, AP reported.
But in signing the Bill Thursday, O'Malley said the measures were aimed at saving lives.
“States with similar licensing provisions have substantially lower gun death rates than states that do not, so if we want better results we have to make better choices, and this legislation is part of that series of the better choices that we are making,” O’Malley said.
Other states include New Jersey, Connecticut, New York, Massachusetts, and Hawaii.
Last month, Delegate Neil Parrott, a Washington County Republican, called the bill unconstitutional and maintained he would fight it if introduced, NBC reported.