The man suspected of shooting dead a US politician and her husband has been arrested following a large-scale manhunt.
Democratic former House speaker Melissa Hortman and her husband were shot and killed in their Minnesota home on Saturday, local time.
Minnesota senator John Hoffman and his wife were also shot at their home a short distance away, but both survived.
Police have arrested 57-year-old Vance Boelter, who they allege had a list of 70 targets at the time of the shooting.
Officials said the arrest followed the "largest manhunt in Minnesota's history".
Asked whether the attacks could be labelled an act of domestic terrorism, they stated it was "way too soon" in the investigation to confirm, but that they were "confident" the shooter had worked alone.
Mr Boelter's car and a hat were found near a wooded area in Sibley County, Minnesota, earlier on Sunday, local time.
Suspect arrested after 'sleepless nights' and 'complex' manhunt
Mr Boelter has been charged with two counts of second-degree murder and two counts of attempted second-degree murder, according to a criminal complaint.
[fbi reward]Drew Evans, superintendent of Criminal Apprehension at Minnesota's Department of Public Safety, said Mr Boelter had been taken into custody in Sibley County.
"There was information provided that he had been seen in the area," he said, adding agents had "converged" on the area following the tip.
Minnesota Governor Tim Walz has thanked law enforcement officers for their "coordination and collaboration" in apprehending Mr Boelter.
"After a two-day manhunt, two sleepless nights, law enforcement have apprehended Vance Boelter," he said.
"That's 48 hours that law enforcement was involved in a complex and dangerous manhunt.
"One man's unthinkable actions have altered the state of Minnesota."
[walz presser] He added the investigation was ongoing.
"A moment in this country where we watched violence erupt ... cannot be the norm," he said, calling on residents to "find common ground" with neighbours.
"This is who Melissa Hortman was."
Officials declined to provide further information on any statements made by Mr Boelter before or after his arrest.
No 'traditional manifesto' in alleged shooter's notebook, police say
Officials have urged people not to speculate on the possible motive behind the shootings.
Writings found in Mr Boelter's car did not match the format of a "traditional manifesto", investigators said.
Along with the list of targets, police said a "notebook" recovered included many "other thoughts" and documents.
They have yet to elaborate further.
Mr Evans said the documents were more related to targets.
"I don't want the public to have the impression that there's this long manifesto that's providing all of this information and details and then associate it with names," he said.
"It's much more about names … and we will work through. And beyond that, I cannot provide details because it's part of the active criminal investigation."
Along with the vehicle, officials found a hat and other items, but investigators did not give further details on what they recovered.
It was also unclear whether Mr Boelter had received any assistance while on the run.
Investigators said they had spoken to several family members, including Mr Boelter's wife.
Suspect allegedly wore fake police uniform before attacks
Police have alleged Mr Boelter donned a latex mask and police uniform in order to gain access to the Hortman and Hoffman homes.
The gunman was exiting the Hortman home as police arrived, wearing a "vest, with Taser, other equipment".
[map]He briefly exchanged fire with officers before fleeing on foot.
An FBI reward of up to $US50,000 ($77,159) was later offered for any information leading to Mr Boelter's arrest.
A dedicated line set up for information received hundreds of tips.
Along with the car later uncovered in Sibley County, what appeared to be a police SUV was found outside the Hortman home with its emergency lights on.
Officials in armoured vehicles combed through farmland and the back roads of Minnesota as part of the search.
Snipers monitored police as they knocked on doors in neighbourhoods close to the suspect's home in Green Isle, Minnesota.
A roadblock established outside the home was lifted late Sunday night.
Minnesota 'not going to be intimidated' by attacks
Senator Hoffman was shot nine times in the attack and has since undergone multiple operations.
His wife Yvette, who was shot eight times, told senator Amy Klobuchar via text message the pair were "incredibly lucky to be alive".
[klobuchar] "[He is] closer every hour to being out of the woods," Ms Hoffman wrote, in screenshots shared by Ms Klobuchar.
"We are gutted and devastated by the loss of Melissa and Mark. We have no words.
"There is never a place for this kind of political hate."
Friends and colleagues have also shared memories of Ms Hortman, the Minnesota House of Representatives' top Democrat, and her husband.
[tim walz]Minnesota representative Leigh Finke called Ms Hortman a "friend to all of us in the caucus".
"She knew all 66 of her members were going to have her care and attention, and she provided it individually and supportively," Ms Finke said.
"She was fierce and she was strong."
Minnesota Attorney-General Keith Ellison, who said he was also on the list of targets recovered by police, called Ms Hortman a "dear friend".
"This guy cannot intimidate us," Mr Ellison told MSNBC.
"We're not intimidated. We are standing firm, we are standing strong. Our beliefs around liberty and justice for all are as strong as ever.
"He can have whatever kind of little list he wants."
"We're going to be safe. We're going to be pragmatic. But we're not going to stop standing up for justice."