A top US immigration official is expected to leave the US city of Minneapolis in what may mark a shift in the White House's tone after the fatal shooting of a second US citizen by federal officers over the weekend.

As Border Patrol Commander Gregory Bovino and some immigration agents leave, President Donald Trump's border tsar Tom Homan will begin leading on-the-ground efforts in city after the fatal shooting of Alex Pretti on Saturday escalated tensions.

Trump's decision may indicate the administration's interest in walking back more aggressive federal action in his nationwide immigration crackdown.

Despite the announcement, online tracking shows immigration raids have continued.

As well as the change in leadership and the reduction in federal agents, there have been other signs of a shifting strategy by the Trump administration in recent days.

Trump had phone calls with Democratic city and state officials that he described positively, a change in tone after attacking them over the weekend. And the president himself has avoided the language used by some of his top aides that sought to blame Pretti for Saturday's tragedy.

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

On Monday, a Republican contender to become state governor dropped out of that election race, calling the enforcement operation in Minnesota an "unmitigated disaster".

That candidate was Chris Madel, a defence lawyer who has provided advice to the agent who earlier this month shot dead another US citizen in Minneapolis, Renee Good.

Bovino was the face of the operation when Pretti - an observer seen filming agents - became involved in a confrontation that ended in Pretti being shot numerous times.

The commander claimed that Pretti intended to "massacre" federal agents - a statement that angered many protesters on the streets.

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 on Saturday.

Eyewitnesses, local officials and the victim's family have challenged that account, pointing out Pretti had a phone in his hand, not a weapon. His parents, meanwhile, have accused the administration of spreading "sickening lies" about what happened.

There is no sign of a gun in Pretti's hand, according to analysis of the available video by BBC Verify.

Bovino has been key to the Trump administration's hard-line approach to immigration enforcement in several cities, active on social media and regularly filming raids and posting promotional videos showing his agents' action.

Homan, who will report directly to the president, advocates for the aggressive immigration enforcement pushed by Trump. But he also has longer-term experience in the role, having worked with immigration and deportations during the Democratic presidency of Barack Obama.

Some media reports suggested Bovino had been let go from his role, but DHS spokesperson Tricia McLaughlin denied that, saying the Border Patrol chief was "a key part of the president's team and a great American".

Tension and frustration over the presence of federal officials remained high in Minneapolis on Monday.

"A lot of people aren't able to work right now, they aren't able to leave their house, they're afraid," said George Cordero, a resident of St Paul, Minneapolis', sister city.

Carol Engelheart, a retired nurse from Minneapolis, said events in the city had left her shaken.

"We need to care about this country, we need to care that we have a Constitution left, and if the people organise and the people stand up, we can do this," she said.

Pretti, a 37-year-old nurse, was the second Minneapolis resident shot and killed by federal immigration officials since their arrival in the state. The first, Renee Good, was killed by an Immigration and Customs Border Enforcement (ICE) agent on 7 January.

Much of the anger in the city and from politicians on both sides of the aisle was directed at Bovino and the Border Patrol agents who were sent to Minneapolis along with ICE agents at Trump's directive. In total, there are approximately 3,000 immigration agents in the city.

Micayla Pretti, Alex Pretti's younger sister, released a statement on Monday, the Associated Press reported, calling her brother "my hero".

"When does this end? How many more innocent lives must be lost before we say enough?" her statement said.

Memorials for Pretti and demonstrations against ICE action continued on Monday night, including one that saw about a hundred people gather outside the hotel Bovino was believed to be staying in and demand that he leave the city. More vigils and demonstrations are planned for the coming days.

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

White House Press Secretary Karoline Leavitt said on Monday that it is the president's "hope and wish and demand for the resistance and chaos" in Minneapolis to end.

During his calls on Monday, Trump spoke to both Minnesota Governor Tim Walz and Minneapolis Mayor Jacob Frey - Democratic leaders who have resisted the immigration efforts and demanded agents be removed from the state. Trump has sharply criticised both men in recent weeks.

Like Trump, the local leaders characterised the talks as positive - a sign that both sides were seeking a way to end their standoff over the president's deportation drive.

Trump said he and Walz were "on a similar wavelength" and said his target was "any and all criminals that they have in their possession".

"The president agreed to look into reducing the number of federal agents in Minnesota and to talk to DHS about ensuring the Minnesota Bureau of Criminal Apprehension is able to conduct an independent investigation, as would ordinarily be the case," Walz said after the call.

Ensuring an independent investigation into Pretti's death has been a central focus for Walz. In its immediate aftermath, local authorities obtained a judicial warrant to gain access to the crime scene to preserve evidence.

In the aftermath of Good's shooting, local and state authorities said they were being kept out of the investigation by federal immigration officials.

Frey meanwhile said he hoped to meet Homan on Tuesday to discuss next steps.

Among the Republicans who have so far shown disquiet over the events in Minnesota are US Senator Ted Cruz, who said on his podcast: "I would encourage the administration to be more measured, to recognise the tragedy."

Another Republican senator and Trump ally, Lindsey Graham, called Trump's decision to send Homan to Minneapolis "a very smart move".

Meanwhile, certain other prominent Republicans have joined opposition Democrats such as Walz to urge the Trump administration to ensure that the investigation into Pretti's killing is a wide-ranging one.

Another Republican senator, John Curtis from Utah, called for a "transparent, independent investigation" into Pretti's shooting.

"Those responsible - no matter their title - must be held accountable," he said. (BBC)

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