Gun sellers have gotten the message that so-called "copycat" assault weapons won't be tolerated in Massachusetts, state Attorney General Maura Healey said Monday.

Speaking to reporters at the Philadelphia hotel where the Massachusetts delegates to the Democratic National Convention are staying, Healey said a spike in sales following last week's announcement that enforcement of the state's ban on assault-style weapons would be stepped up has since subsided.

"The action we took was about closing the loophole, making clear that people understood the law, and making clear that people understood that we were going to enforce the law," Healey said, according to State House News Service. "The good news is that while sales were up the day of the announcement, sales continued to drop precipitously over the next few days.

"We continue to monitor sales, but I think what's clear is that gun dealers, gun manufacturers, have gotten the message that this subset of weapons cannot be available under existing law. I'm not creating new law. This is under existing law."

Hundreds of gun rights activists and Republican lawmakers rallied on Beacon Hill Saturday, protesting Healey's new gun control efforts. During the rally, the protesters wore T-shirts and held signs comparing Healey to Adolf Hitler and Joseph Stalin.

Jim Wallace, executive director of the Gun Owners Action League of Massachusetts, which organized the protest, said lawmakers have had a chance to add guns to the assault weapons ban.

"These laws were passed in 1998, they were redone in 2004, then they were reviewed in 2014, so the Legislature is already fine with what is going on," Wallace was quoted by State House News Service. "What other reason would a person unilaterally decide, I'm going to change the rules overnight?"

Asked about enforcement actions and whether anyone had been cited since the crackdown, Healey said, "Not yet," State House reported.