(ECNS) - A federal immigration enforcement operation in Minneapolis has triggered widespread criticism of President Donald Trump's immigration policies, drawing rebukes from former U.S. presidents Barack Obama and Bill Clinton and intensifying debate over federal enforcement tactics.

During the operation on Saturday, U.S. Border Patrol agents fatally shot Alex Pretti, a 37-year-old ICU nurse, in Minneapolis. 

In a joint statement issued Sunday, Barack and Michelle Obama said Pretti's killing should be a "wake-up call" for the nation, warning that America's core values "are increasingly under assault." The Obamas did not address Trump directly, but framed the shooting as part of a broader erosion of civil liberties under aggressive federal enforcement.

Bill Clinton delivered a more direct condemnation hours later, saying peaceful protesters under the current government "have been arrested, beaten, teargassed, and most searingly, in the cases of Renee Good and Alex Pretti, shot and killed."

"All of this is unacceptable," Clinton said, urging Americans to "stand up, speak out," and warning: "If we give our freedoms away after 250 years, we might never get them back."

Pretti was killed less than three weeks after another Minneapolis resident, Renee Good, was fatally shot by an immigration officer on Jan. 7.

Trump administration officials said Pretti intended to harm agents, citing a holstered handgun found on him. However, video of the incident, widely circulated and verified by U.S. media, shows Pretti never drawing a weapon and being shot moments after he was sprayed with chemical irritant and thrown to the ground.

The White House has blamed Minnesota's Democratic leadership for what Trump called "Democrat ensued chaos" in so-called"Sanctuary Cities."

Speaking to the Wall Street Journal, Trump declined twice to say whether the officer acted appropriately, saying only: "We're looking. We're reviewing everything."

Criticism has extended beyond Democrats. Senator Bill Cassidy, a Louisiana Republican, called the killing "incredibly disturbing" in a social media post, saying "the credibility of ICE and DHS is at stake."

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

Minnesota Governor Tim Walz disputed federal claims that Pretti posed a threat, accusing officials of "spinning stories and putting up pictures." Minneapolis Police Chief Brian O'Hara said Pretti was an American citizen with no criminal record and a valid firearms permit, noting that Minnesota law allows permitted citizens to carry handguns openly in public.

Gun-rights groups have also raised alarms. The Minnesota Gun Owners Caucus said it was "deeply concerned" by efforts to justify the shooting based on Pretti's legal possession of a firearm, stressing that "every peaceable Minnesotan has the right to keep and bear arms, including while attending protests."

(By Zhang Jiahao)