A massive manhunt is under way after another Democrat was targeted by the same gunman.
A Democratic state representative and her husband have been shot and killed in a "politically motivated assassination" in Minnesota, with the suspected gunman on the run.
Melissa Hortman and her husband Mark were both killed in the attack in their home early on Saturday morning (Sunday AEST).
Minnesota State Senator John Hoffman and his wife were also targeted by the same individual and each shot multiple times in a separate incident, Minnesota Governor Tim Walz said. They have undergone surgery and are alive.
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The suspect has been identified as 57-year-old Vance Boelter, a director at security company Praetorian Guard Security. Officials said he had US military training.
"The Hoffmans are out of surgery at this time and receiving care, and we are cautiously optimally optimistic, they will survive this assassination attempt," Walz said.
Both legislators are members of the Minnesota Democratic–Farmer–Labor Party.
The suspect is at large and a massive manhunt is underway, officials said at the news conference.
The Brooklyn Park Police Department, along with other law enforcement agencies from the Hennepin County Sheriff's Office, the Minnesota Department of Public Safety State Patrol, the FBI and BCA are now actively engaged in a manhunt for Boelter, who they believe is responsible for both shootings.
FBI Deputy Director Dan Bongino said the FBI was "fully engaged" on the ground.
Bruley also said a "manifesto" identifying "many lawmakers and other officials" was found when law enforcement searched Boelter's vehicle.
A law enforcement official briefed on the matter told CNN law enforcement found a hit list in the Minnesota suspect's car that contained nearly 70 names. The names included abortion providers, pro-abortion advocates and lawmakers in Minnesota and in other states, the official added.
President Donald Trump has been briefed on the shootings and said Attorney General Pam Bondi and the FBI were leading the investigation, adding that anyone involved would be "prosecuted to the fullest extent of the law".
Police were first called around 2am local time on Saturday with reports that someone had shot Hoffman and his wife.
Police responded to their home and provided life-saving measures before the couple was transported to the hospital, according to Drew Evans, the Minnesota Bureau of Criminal Apprehension superintendent.
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At 3.35am, another call came in when officers were proactively checking on Hortman's home.
When Brooklyn Park police officers arrived they noticed that there was a police vehicle in the driveway with emergency lights on and what appeared to be a police officer at the door, coming out of the house, officials said.
That individual immediately fired a weapon at them, Evans said, and exchanged gunfire took place during which the suspect was able to escape.
Authorities are searching for a male wearing a vest with Taser, a badge and other equipment similar to that of a police officer, according to Bruley. The suspect is on foot.
"If somebody comes to the door and they knock on the door claiming to be a police officer, please do a couple things: one, call 911 and confirm that the officer belongs there. If they are a police officer, dispatch will be able to confirm that that person is police officer," Bruley said, addressing the community.
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"Also, we informed all our officers in Brooklyn Park that they are not to approach anybody by themselves. They're approaching pairs, meaning two officers."
Walz has activated the State Emergency Operations Centre and a cross-jurisdictional Joint Information Centre has been established as the manhunt continues, according to the governor's spokesman Teddy Tschann.
"Local law enforcement in Champlin and Brooklyn Park have the full resources of the State of Minnesota behind them. We are monitoring the situation closely and will share more information soon," Walz said in a post on X.
The Brooklyn Park Police Department issued a shelter-in-place order for an area surrounding Edinburgh Golf Course on Saturday morning, according to the City of Brooklyn Park.
The governor said the Minnesota Department of Public Safety and local law enforcement were on the scene.
"This is a stunning act of violence. I'm thankful for all the law enforcement who are responding in real time," US Senator Klobuchar said in a post on X.
"My prayers are with the Hortman and Hoffman families. Both legislators are close friends and devoted to their families and public service."
Former Congresswoman Gabby Giffords, now the head of national gun violence prevention organization GIFFORDS, said in a statement on Saturday that she was "horrified and heartbroken by last night's attack on two patriotic public servants."
"My family and I know the horror of a targeted shooting all too well. An attack against lawmakers is an attack on American democracy itself," Giffords said.
"Leaders must speak out and condemn the fomenting violent extremism that threatens everything this country stands for.
Giffords was one of 13 people wounded in an Arizona supermarket parking lot in 2011.
Congressional leaders condemned the political violence in posts on social media.
"Such horrific political violence has no place in our society, and every leader must unequivocally condemn it. Our prayers are with the Hortman and Hoffman families as well as the people of Minnesota during this tragic time," House Speaker Mike Johnson said in an X post.
House Minority Leader Hakeem Jeffries said in a post on X: "The targeted shootings of Minnesota Senator John Hoffman and State Rep. Melissa Hortman are deeply disturbing. Violence is never acceptable. Praying hard for the victims and all who have been affected."