Gun owners, dealers and activists are already calling for protests in the wake of Attorney General Maura Healey’s announcement she’d be stepping up enforcement of the state’s assault weapons ban.

That crackdown is an effort to curb sales of “copycat” assault weapons, an estimated 10,000 of which were sold in Massachusetts last year alone.

The state considers a firearm a copycat of those weapons banned under a state assault weapons ban if the gun’s internal operating system is essentially the same as those of a banned weapon, or if the gun has key functional components that are interchangeable with those of a banned weapon.

"I've been looking at the reactions that's been going on in social media and text messages I've been getting, and I think that Maura Healey really stepped in it," Massachusetts Gun Rights President Christopher Pinto said.

Protests outside the State House are planned for Thursday and Saturday, with organizers describing Healey's actions as unconstitutional.

Less than 24 hours after the announcement, more than 15,000 people had signed an online petition calling on Gov. Charlie Baker to overturn Healey's decision. Over 500 joined a Facebook group calling for her to be recalled or impeached.

"This is like the day of infamy for Maura Healey. She's going to awaken the sleeping giant of gun owners in Massachusetts,” Pinto added. “There's nearly half a million of us in Massachusetts - Republican, Democrat and Independent – and she's really woken up a sleeping giant, and her chances of getting elected governor or keeping her office could be over."

In a statement earlier this week, Healey said that the guns in question were “the weapon of choice for mass shooters.”

“We will do everything we can to prevent the kinds of tragedies here that have occurred in places like Orlando, San Bernardino, Newtown and Aurora,” she said in a statement.

Gov. Charlie Baker told WGBH Radio Thursday that Healey has the "authority and the jurisdiction" to issue such a notification.

"If people are in fact selling weapons that violate the Massachusetts assault weapon ban, then that should be dealt with and people should do something about it," he said. "I think the big issue, especially in the short term, is going to be the confusion around which weapons this applies to and which weapons it doesn't apply to."

Reporting from State House News service contributed to this report.