US President Donald Trump says his administration is "reviewing everything" after the fatal shooting by immigration agents of 37-year-old intensive care nurse Alex Pretti in Minneapolis on Saturday.

In his comments to the Wall Street Journal, Trump also indicated that he would eventually withdraw agents from the city. But he did not give a time frame.

Protests continued in Minneapolis and other US cities on Sunday, as Minnesota Governor Tim Walz warned that America was at an "inflection point".

The facts around the incident - the second fatal shooting by agents of a US citizen in recent weeks - have been hotly contested, setting up a fresh confrontation between state and federal officials.

The administration has defended the officer who shot Pretti. Homeland Security Secretary Kristi Noem said Pretti was shot because he was "brandishing" a gun.

Local authorities deny this, adding that the gun was legally registered and that Pretti was shot after the firearm was removed.

The Wall Street Journal reported that Trump was directly asked twice whether the agent had done the right thing. He responded: "We're looking, we're reviewing everything and will come out with a determination."

He also told the newspaper: "I don't like any shooting. I don't like it." He added: "But I don't like it when somebody goes into a protest and he's got a very powerful, fully loaded gun with two magazines loaded up with bullets also. That doesn't play good either."

The Trump administration is facing pressure from some prominent Republicans, who have joined opposition Democrats in calling for a wide-ranging investigation.

Senator Bill Cassidy said the probe should involve both federal and state officials. Congressman James Comer, an ally of Trump, suggested that the president should consider withdrawing immigration agents from Minneapolis and sending them elsewhere, telling Fox News that the city's mayor and state governor were putting them in harm's way, and "there's a chance of losing more innocent lives".

In his comments to the Wall Street Journal, Trump said of the deployment: "At some point we will leave. We've done, they've done a phenomenal job."

Multiple vigils were held for Pretti in Minneapolis over the weekend.

Lifelong resident Pege Miller, 69, was among those who gathered on Sunday afternoon to pay her respects and protest against the Immigration and Customs Enforcement agency (ICE).

"I'm tired of protesting," she told the BBC. "We can't comprehend how this is happening. Why are we letting this happen?"

Demonstrators of all ages were chanting "No more Minnesota nice - Minneapolis on strike" and "ICE out now" before they began moving through the city streets.

"This is not the America I fought for," said one man the BBC spoke to, who asked not to be named.

Protests have spread to other US cities, including New York, Chicago, Los Angeles and San Francisco.

The chief executives of more than 60 Minnesota-based businesses, including 3M, Best Buy and Target have also signed an open letter calling for "an immediate de-escalation of tensions" and for local and federal officials "to work together to find real solutions".

Minneapolis Police Chief Brian O'Hara told the BBC that state officers were blocked from accessing the scene of Pretti's shooting by federal agents, despite securing a search warrant.

He added that all levels of law enforcement in Minnesota have been working with federal law enforcement "for several years", and that the unfolding situation in Minnesota was hampering agencies' ability to continue such investigations.

Lawmakers continue to be divided over the shooting of Pretti, as well as his second Amendment right to bear arms. It is legal in Minnesota to carry a handgun in public if you have a permit.

The administration has characterised the Minneapolis operation as a public safety effort aimed at deporting criminals illegally in the US. It has also described Pretti as a "domestic terrorist".

Critics warn migrants with no criminal record and US citizens are being detained, too.

Pretti's family issued a statement in response to the comment, saying: "The sickening lies told about our son by the administration are reprehensible and disgusting".

They added that he had no interaction with law enforcement beyond a handful of traffic tickets. According to Associated Press (AP), court records show he had no criminal record.

"Please get the truth out about our son. He was a good man," his family said in the statement.

On Sunday, Tim Walz said: "I don't care if you are conservative and you are flying a Donald Trump flag, you're a libertarian, don't tread on me, you're a Democratic Socialist of America. This is an inflection point, America.

"If we cannot all agree that the smearing of an American citizen and besmirching everything they stood for and asking us not to believe what we saw, I don't know what else to tell you."

Backlash against the Trump administration's crackdown is growing, including from within the Republican party.

Oklahoma Governor Kevin Stitt told CNN that people were watching fellow Americans being shot on television and that "federal tactics and accountability" had become a growing concern for voters.

Louisiana Senator Bill Cassidy said the Minneapolis shooting was "incredibly disturbing" and "the credibility of ICE and DHS are at stake."

Democrats have responded by threatening to block a key government financing package if it contains funds for the Department of Homeland Security, of which ICE is a part, raising the prospect of another government shutdown.

Former Democratic Presidents Bill Clinton and Barack Obama have both criticised the situation in Minneapolis, with the former described events in Minneapolis as "horrible scenes" that "I never thought would take place in America."

Few Minnesotans the BBC spoke to said they supported ICE operations, but several polls suggest about half of voters nationwide support President Trump's efforts to deport those living in the US illegally.

Other polls indicate voters are split on how Trump is carrying out that crackdown on undocumented immigrants.

Meanwhile on Sunday evening Trump demanded in a post on Truth Social that Walz and Frey, as well as "EVERY Democrat Governor and Mayor in the United States" must "formally cooperate with the Trump Administration to enforce our Nation's Laws, rather than resist and stoke the flames of Division, Chaos, and Violence".

He also called on US Congress to end sanctuary cities, which he alleged were the cause of "all these problems".

The term 'sanctuary city' is commonly used to describe places in the US that limit their assistance to federal immigration authorities.

Trump's posts followed remarks from White House Press Secretary Karoline Leavitt, where she condemned Walz as wanting chaos, and encouraging "left-wing agitators to stalk and record federal officers in the middle of lawful operations".

Federal agents shot and killed Pretti in Minneapolis on Saturday, and videos have since emerged showing a scuffle between Border Patrol agents and Pretti just before the shooting.

The Department of Homeland Security (DHS) said the agents fired in self-defence after Pretti, who they say had a handgun, resisted their attempts to disarm him.

Eyewitnesses, local officials and the victim's family have challenged that account, pointing out he had a phone in his hand, not a weapon.

O'Hara, the Minneapolis police chief, told the BBC that Pretti was a lawful gun owner with no criminal record other than traffic violations.

In a statement, it said: "Responsible public voices should be awaiting a full investigation, not making generalisations and demonising law-abiding citizens."

US Border Patrol commander Greg Bovino said earlier that at the time of the shooting, ICE agents were looking for a man named Jose Huerta Chuma during a "targeted" operation, and that Chuma's criminal history includes domestic assault, intentional infliction of bodily harm and disorderly conduct.

The Minnesota Department of Corrections (DOC) has since rebutted those claims and said that Huerta had never been in Minnesota DOC custody and public records reflected only misdemeanour-level traffic offences from more than a decade ago.

The latest shooting follows weeks of tensions between the Minnesota authorities, federal agents and protesters who have taken to the streets to observe the agents during their anti-immigration raids.

Earlier this month, an ICE agent shot dead Renee Good, a 37-year-old Minneapolis resident who was taking part in such an observation.

In a statement to CBS News, the BBC's US media partner, Good's family law firm Romanucci & Blandin urged all Americans to "trust their own eyes as they interpret the horrific video" of Pretti's shooting.

Trump's crackdown in Minneapolis was launched in December after some Somali immigrants were convicted in a massive fraud of state welfare programmes. The state is home to the largest community of Somali immigrants in the US.

ICE agents have the power to stop, detain and arrest people they suspect of being in the US illegally. (BBC)

Update news