Who was Alex Pretti, the intensive care nurse shot dead in Minneapolis?

Family members have paid tribute to 37-year-old intensive care nurse Alex Pretti, who was shot dead by federal immigration agents in Minneapolis on 24 January.

Pretti was a hero who "touched more lives than he probably ever realised", his sister, Micayla Pretti, told the Associated Press.

The family has condemned what they said were "disgusting lies" being told about the late man.

Pretti - who has also been described as a lover of the outdoors and mountain biking - is understood to have joined protests after Renee Good, also 37, was shot dead by an federal agent in the same city earlier this month.

An earlier family statement from 25 January, also quoted by AP, said Pretti was upset over US President Donald Trump's crackdown on immigration in the city.

His mother, Susan Pretti, said her son was also concerned about the Trump administration's rollback of environmental regulations.

"He hated that, you know, people were just trashing the land," she said. She added: "He was an outdoorsman. He took his dog everywhere he went. You know, he loved this country, but he hated what people were doing to it."

On Sunday, Minnesota Governor Tim Walz described Pretti as "someone who went to work to care for veterans, someone who was a valued co-worker, someone who relished and lived in this state in a big way, whether it was outdoor activities or being down there on the street as a First Amendment witness to what ICE is doing to this state."

Videos have 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.

BBC Verify analysed multiple videos showing the moments just before the shooting. They show Pretti filming ICE agents with his mobile phone. One of the agents pushes another person over, and Pretti then stands between that person and the agent.

The agent pepper sprays him in the face and as he tries to help the woman on the floor, more agents join and he is wrestled to the floor. He is visibly not holding a gun.

An agent in a grey jacket can be seen reaching to remove something from Pretti's waist. He then turns away from Pretti, now holding what appears to be a pistol in his right hand, which was previously empty.

Less than a second after this, an agent shoots Pretti. Ten shots in total are heard.

Police have said Pretti was a legal gun owner. Under Minnesota law, citizens can legally carry a concealed handgun in public, if they have a permit.

In filed testimony, two witnesses challenged the DHS account of what happened, both saying they did not see Pretti brandish a weapon.

But Deputy Attorney General Todd Blanche told NBC's Meet the Press on Sunday that the videos were unclear and "there is a lot we don't see" in them so it was important to have an investigation.

Pretti's family said he had no interaction with law enforcement beyond a handful of traffic tickets. He had no criminal record, AP reported.

Responding to videos that suggested their son was a "domestic terrorist," Pretti's family said: "The sickening lies told about our son by the administration are reprehensible and disgusting."

Pointing to the video evidence, which does not show a gun in Pretti's hand when he was tackled by federal agents, they added: "Please get the truth out about our son. He was a good man."

President Donald Trump, who ordered the immigration crackdown, has since asked the top US immigration official in Minneapolis, Gregory Bovino, to leave the city.

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

A US citizen born in Illinois, Pretti grew up in Green Bay, Wisconsin, where he played football, baseball and ran track for Preble High School. He was a boy scout and sang in the Green Bay Boy Choir.

He went to the University of Minnesota, graduating in 2011 with a bachelor's degree in biology, society and the environment, according to his family.

He worked as a research scientist before returning to education to qualify as a registered nurse. He went on to work in the ICU at the Minneapolis Veterans Affairs (VA) hospital.

The statement from Micayla Pretti said that all her brother "ever wanted was to help someone - anyone".

"Alex always wanted to make a difference in this world, and it's devastating that he won't be here to witness the impact he was making," she added.

"Through his work at the VA caring for the sickest patients, and passion to advance cancer research, he touched more lives than he probably ever realised."

Doctor Dmitri Drekonja, who worked with Pretti, told ABC News the pair had bonded over their interest in mountain biking and would compare notes on which trails to ride.

"He was the type of person you enjoyed being around and the notion that this helpful, smiling joking guy was being labelled a terrorist? It's galling," he said.

Neighbours described Pretti as quiet and warmhearted.

"He's a wonderful person," said Sue Gitar, who lived downstairs from the nurse and said he moved into the building about three years ago. "He has a great heart."

Pretti lived alone and worked long hours as a nurse, but he was not a loner, his neighbours said.

"I never thought of him as a person who carried a gun," said Gitar.

Pretti was a Democratic voter and had taken part in the wave of street protests after George Floyd was killed by a Minneapolis police officer in 2020, his ex-wife told AP.

She said that he was someone who may shout at law enforcement officers at a protest but had never known him to be physically confrontational.