Virginia Gov. Ralph Northam ordered a special legislative session to address gun violence Tuesday, four days after a public works employee killed 12 people in a shooting rampage at a municipal building in Virginia Beach.

"The nation is watching," Northam said at a new conference. "We must do more than give our thoughts and prayers. We must give Virginians the action they deserve."

Northam said he would seek universal background checks, bans on assault weapons and suppressors, extreme-risk protective orders, child access prevention and other restrictions.

"It is wrong that we now view these mass shootings as the new normal," Northam said. "It is past time to change."

Northam, a Democrat, said he had previously asked the Republican-led Legislature for a number of tighter gun restrictions. But he said lawmakers repeatedly rejected his requests.

"This weekend's tragedy ... must instill in us a new urgency to act," he said. "If we can save one life because we acted now, it is worth it."

Larry Sabato, director of the Center for Politics at the University of Virginia, said the tragedy at Virginia Beach could have an impact on Northam's cause. The GOP holds a slight edge in the state Senate and General Assembly, but all seats are on the ballot in November.

"Quite a list of gun control measures," Sabato tweeted. "But post-VA Beach, a majority of the public almost certainly favors every one. Urban-suburban legislators who vote no in the upcoming special session will hand a powerful weapon to their November opponents."

Carl Tobias, a law professor at the University of Richmond, agreed that it was possible Northam could see some success.

"The General Assembly could pass some measures if the members have the will to work in a bipartisan, open way on pragmatic, effective legislation," Tobias told USA TODAY.

The gun-violence prevention group Brady applauded Northam's call for restrictions. Kris Brown, Brady president and a Virginia native, said Virginia lawmakers have consistently "put profits over people" and sided with the gun lobby.

"Now, they have an opportunity to make this right," Brown said.

Northam, a physician, rejected claims that it is "too soon" after the tragedy to address the issues. Delays, he said, would only result in more deaths. Northam did not immediately reveal the dates for the special session.

"As an Army doctor, I have seen first hand what a bullet does to a body," he said. "And I saw it again this weekend. I can't imagine the devastation these families are suffering."

Lt. Gov. Justin Fairfax and Attorney General Mark Herring were among state leaders who also appeared at the news conference, echoing their fellow Democrat's call for action. The three leaders have each been embroiled in controversy in recent months.

In February, a blackface photo surfaced from Northam's medical school yearbook. Northam initially apologized, then said he wasn't in the photo. Days later, Fairfax was accused of sexual assault, which he adamantly denies, stemming from a 2004 encounter. That drew calls for his ouster. Then, Herring admitted he, too, donned blackface in the 1980s.

Calls for their resignations have eased in recent weeks, and Northam has been a face of the response to the shooting.

The suspected shooter, a civil engineer who worked for the city for 15 years, was fatally shot after a standoff with police. The shooting, the nation's deadliest of the year, unfolded Friday around 4 p.m. when the suspect shot the first victim outside Building 2, a three-story brick structure with about 400 municipal workers.

Police say the man attached a suppressor, also known as a silencer, to the .45-caliber handgun that he fired on three floors of the building where he worked. Virginia is among 42 states that allow residents to purchase and possess suppressors, though some cities – including Virginia Beach – prohibit them.

Authorities said the suspected shooter legally bought multiple firearms recently, but they have not said how he got a suppressor.

Northam traveled to Virginia Beach hours after the shooting, comforting survivors and helping coordinate the response to the shooting. He also spoke with President Trump and lobbied at a press conference last week for tighter gun controls.

Contributing: Brad Zinn and Kristin Lam, USA TODAY