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 timeframe.

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.

Pretti's family also explained he owned a handgun and had a permit to carry a concealed handgun in Minnesota - but they had never known him to carry it.

Local police have said he was a lawful gun owner with a permit to carry. It is legal in Minnesota to carry a handgun in public if the owner has a permit.

The Wall Street Journal reported that Trump was directly asked twice whether the agent had done the right thing during the incident. 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.

The terms of the investigation became a sticking point in the case of Renee Good, who was the first US citizen shot dead by a federal agent in Minneapolis earlier this month. The incident is being looked into by the FBI, after Minnesota officials withdrew amid a row with federal personnel.

It appears that another dispute could unfold during the probe into the second fatal shooting. On Sunday, Minneapolis Police Chief Brian O'Hara told the BBC that state officers were blocked from accessing the scene by federal agents, despite securing a search warrant.

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

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.

US Border Patrol commander Greg Bovino previously said that at the time of the shooting, Immigration and Customs Enforcement (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 mis

Among the Republicans who have voiced disquiet over the events are Oklahoma Governor Kevin Stitt, who 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.

Senator Bill Cassidy said the probe into the second fatal shooting should involve both federal and state officials. He said the shooting had been "incredibly disturbing" and that "the credibility of ICE and DHS are at stake".

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."

For their part, Democrats in Congress have responded by threatening to block a key government financing package if it contains funds for the DHS - raising the prospect of another federal 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."

The National Rifle Association (NRA) - which is typically aligned with Trump - has also pushed back at Trump, joining other US gun lobby groups in calling for a full investigation. In a statement, it said: "Responsible public voices should be awaiting a full investigation, not making generalisations and demonising law-abiding citizens."

Multiple vigils were held for Pretti in the city 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".

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, Governor 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."

A protest on Sunday in Chicago - one of the other cities to which protests have spread