WASHINGTON, DC, United States (AFP) — A manhunt was underway Saturday for a gunman who shot two Democratic state lawmakers in Minnesota, killing one and her husband and wounding the other, in what the northern US state’s governor said were politically motivated attacks.

The shootings came as deep political divisions have riven the United States, the same day that tens of thousands of protesters across the country took to the streets against the policies of Republican President Donald Trump.

Authorities named the assailant as 57-year-old Vance Luther Boelter, who was still at large and considered “armed and dangerous”.

“We believe he’s working to potentially flee the [Minneapolis-St Paul] area,” said Drew Evans, superintendent of the state Bureau of Criminal Apprehension, at a press conference.

Boelter had been spotted Saturday morning in the Minneapolis area on video surveillance footage obtained from a business, the official said.

Evans said authorities were still investigating the suspect’s motives, and did not know if additional people were involved in the attacks.

Trump and US Attorney General Pam Bondi decried what they called “horrific violence” and said perpetrators would be prosecuted to “the fullest extent of the law”.

State Representative Melissa Hortman — the former speaker — and her husband Mark were killed at their home in the Minneapolis suburb of Brooklyn Park, Governor Tim Walz told an earlier press conference.

State Senator John Hoffman and his wife Yvette were shot and wounded at their home in nearby Champlin, the governor said, his voice breaking with emotion.

“This was an act of targeted political violence,” Walz told reporters. “Peaceful discourse is the foundation of our democracy. We don’t settle our differences with violence or at gunpoint.”

Evans said Hoffman was out of surgery and “in stable condition” but that he had suffered “significant injuries”.

The state official said Hoffman and his wife were shot first, and as police investigated, Hortman and her husband were shot about 90 minutes later.

The gunman was able to escape during an exchange of fire with officers near Hortman’s residence, Evans said.

Praetorian Guards Security Services, a home security company, described Boelter on its website as its director of security patrols.

In both attacks, authorities believe the assailant was impersonating a law enforcement officer.

An anti-Trump rally in Minneapolis — part of the national wave of “No Kings” protests planned for Saturday — was cancelled after police issued a shelter-in-place order because of the shootings.

Flyers for the protests were found in the suspect’s car, as well as a manifesto that named numerous politicians and state officials, police said.

Tensions were high across the country, and in Texas the authorities said they evacuated the state capitol complex following a, “credible threat towards state lawmakers planning to attend a protest later today”.

In Brooklyn Park, where Hortman lived, authorities lifted a shelter-in-place order Saturday afternoon, saying that while the suspect remained at large there was “reason to believe he is no longer in the area”.

The United States has been deeply divided since Trump returned to the White House in January.

The Republican president has drawn criticism from Democrats over his harsh immigration policy, his assault on universities and the media, and a perceived flouting of limits on executive power as he pushes his agenda.

“At this precipice moment we’re on, this tragic act here in Minnesota should serve as a reminder to all of us,” Walz said.

“The democracy and the debates in the halls of Congress, in state houses, in school boards, is a way to settle our differences peacefully and move society to a better place.”