An online fundraiser benefiting the family of Alex Pretti had raised nearly $600,000 by Sunday afternoon, a day after federal agents killed the US citizen and nurse in Minneapolis in a shooting that ignited another round of street protests against Donald Trump’s administration and its immigration crackdown in the city.

In a substantial indication of public sentiment, the “Alex Pretti is an American Hero” campaign on the GoFundMe platform surpassed its goal of $20,000 quickly after organizer Keith Edwards launched it on Saturday.

A statement attributed to Edwards on Saturday maintained that the campaign’s purpose was “to support the loved ones [Pretti] leaves behind with immediate needs” after he was “executed on the streets of Minneapolis”. Another statement from Edwards on Sunday said he had managed to get GoFundMe to make Pretti’s father, Michael, the beneficiary of the campaign – “so their family now has direct access to the funds raised”.

“Thank you all so much for your support,” Edwards also wrote as donations came in from about 15,500 users.

GoFundMe didn’t immediately respond to a request for comment on Sunday.

Pretti, 37, was a registered nurse working in the intensive care unit at the Minneapolis VA Health Care System, which serves veterans.

Videos circulating online on Saturday showed Pretti directing traffic and filming federal immigration agents who descended on Minneapolis at the behest of the Trump White House.

In one of the videos, Pretti held up his phone in his right hand, with his left hand empty. Other videos show him coming to the defense of a legal observer who was shoved to the ground by a federal officer. That officer then sprays Pretti with a chemical agent, repeatedly, before tackling him to the street with other agents.

As the officers held him down and hit him, one of them reached to Pretti’s lower back and stepped away with what appeared to be a gun. Video captured one of the agents then shouting: “Gun! Gun!”

Another officer pulled a gun out and evidently shot Pretti once at close range. A second officer pointed a gun at Pretti as he and his colleagues stepped back, and a volley of 10 more shots erupted, video evidence showed.

Pretti was legally permitted to carry a gun, and none of the video evidence – taken from multiple angles – depicted him ever brandishing one.

In a statement to Minneapolis news outlet Kare 11, Pretti’s father and mother, Susan, described themselves as “heartbroken but also very angry”. They dismissed what they called “sickening lies” from Trump administration officials after US homeland security secretary Kristi Noem on Saturday floated the observably false accusation that Pretti was shot dead upon approaching federal officers while brandishing a gun.

Noem also accused Pretti of harboring an intent “to kill law enforcement”, prompting his parents to say in their statement: “Alex is clearly not holding a gun when attacked by Trump’s murdering and cowardly [immigration] thugs.

“Please get the truth about our son. He was a good man.”

Pretti’s killing came 17 days after Renee Nicole Good, also a 37-year-old American citizen, was shot dead in Minneapolis by a federal immigration officer, with video showing her trying to drive away from him. A GoFundMe campaign meant to financially support Good’s family raised more than $1.5m before organizers closed it two days after her shooting death.

Street protests met both Good and Pretti’s slayings, along with widespread calls for the officers at the center of the cases to be held accountable.