Three firefighters have died and two others have been injured Saturday while they tackled blazes on the Colorado-Utah border, the U.S. Wildland Fire Service has announced. The agency said the crew members had been part of an interagency response to the Knowles and Gore fires.

“The U.S. Wildland Fire Service stands united with the USDA Forest Service in grief and in our unwavering support for the loved ones left behind,” the service said in a statement on Facebook. “Their bravery, dedication, and sacrifice will never be forgotten.”

In a press release, the Department of the Interior said that the five firefighters were involved in a “burnover incident”, which refers to when officials are unable to find an escape route, so have to shelter as best they can while a fire passes directly over them. The department said the two firefighters who survived were being treated for burn injuries.

Fires in Utah, Colorado and Arizona have been intensifying, thanks to days of low humidity, high temperatures and strong winds. The conditions have pushed fire behavior to extremes not commonly seen in the region, stretching resources and forcing the governors of both Utah and Colorado to declare emergencies.

Cottonwood fire not yet contained

The biggest blaze is the Cottonwood Fire, burning in rugged terrain in southern Utah’s Beaver County, which has grown to more than 144 square miles and remains entirely uncontained. It is currently the largest wildfire burning anywhere in the United States.

It has already severely damaged the Eagle Point ski resort and destroyed summer cabins. Damage assessments were underway Saturday, though no final estimates of destroyed structures were yet available.

On Saturday, hundreds of residents in the towns of Marysvale, Junction and Circleville were placed on notice to leave as conditions worsened.

Also burning is the Snyder Fire, covering more than 28,000 acres. It began as the Snyder Mesa Fire on Saturday in east Utah’s Grand County, but later combined with the smaller Jones and Knowles Fires in Colorado.

Alyssa Mason, a spokesperson assigned to the Cottonwood Fire, told NPR that crews this weekend had been dealing with single-digit humidity and wind gusts of around 45 miles per hour, on top of fuel moisture readings between 2 and 8 percent.

Rep. Julia Letlow won the Republican primary runoff for Senate in Louisiana, NBC News projects, defeating state Treasurer John Fleming in another victory for President Donald Trump’s slate of preferred candidates.

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Trump endorsed Letlow early in the race, which went to a runoff after none of the GOP candidates won a majority of the initial primary vote on May 16. Trump waded into the state in an effort to oust GOP Sen. Bill Cassidy, who voted to convict Trump on impeachment charges following the Jan. 6, 2021, Capitol riot.

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Letlow was the top vote-getter in the first-round primary, winning 45%, followed by Fleming at 28%. Cassidy won just 25% and did not qualify for the runoff.

Letlow will be in a strong position to win in November in the solidly Republican state, which Trump carried by 22 points in 2024. Democrat Jamie Davis, a farmer, easily won the Democratic Senate nomination Saturday night.

Letlow has pledged to be a strong supporter of the president’s policies.

“I promise you this: When I get to the United States Senate, I will never back down from fighting for your America First agenda,” Letlow told the president during a telerally with Trump on Thursday night.

Letlow framed the race as the choice between “a real conservative fighter in the Senate, or whether we are going to send another career politician who does not want to save our country.” She touted her support for eliminating the Senate filibuster to help pass the Save America Act, a Trump-backed measure to overhaul U.S. election laws.

Fleming also tried to make the case that he was the staunchest Trump ally in the race, taking aim at Letlow’s past support for diversity, equity and inclusion policies and foreign aid. Letlow told NBC News earlier this year that she reversed her position on DEI when she “saw it for what it was” and has since been “fighting against it.”

But Trump’s backing helped boost Letlow, who also had help on the airwaves from allied super PAC.

She also touted endorsements from other top Louisiana Republicans, led by Gov. Jeff Landry. House Majority Leader Steve Scalise and Rep. Clay Higgins also backed Letlow.

Letlow is expected to join the Senate after serving nearly three terms in the House, where she also served on the powerful Appropriations Committee. She first came to Congress in 2021 after winning a special election following the death of her late husband. Luke Letlow, a former congressional aide who won a House election in 2020, died of Covid before he was sworn into office.

Even before the Supreme Court ruled Thursday that President Trump has broad power to deport hundreds of thousands of migrants living legally in the U.S. under temporary protected status, David Bier feared the U.S. was slipping toward a demographic cliff.

“We’re destined to be there, in short order, there’s no question,” Bier said. “We’re already seeing a situation where most counties in the United States had more deaths than births.”

An expert on population and immigration at the libertarian Cato Institute, Bier believes the U.S. is beginning to look more like China, Italy and South Korea — nations that face rapid aging and population decline are seen as a crisis.

U.S. birthrates have been declining for decades. There are far too few children born each year to maintain a stable population.

Until last year, high rates of foreign immigration largely offset that trend. But for the first time since the 1930s, during the Great Depression, the U.S. now faces record low birthrates and low numbers of migrants at the same time.

“Our higher birthrates of a century ago are not coming back. There’s no way to have a sustainable fiscal and economic situation that doesn’t involve immigration,” Bier said.

Trump’s legal fight to end temporary protected status for hundreds of thousands of Haitians, Syrians and others living in the U.S. legally is only one part of a wider administration effort to squeeze immigration.

The Supreme Court also ruled this week that the administration has authority to block most asylum seekers from entering the country. Federal agents have also conducted raids in cities across the U.S., to accelerate deportations.

Last month, Trump issued an executive order that could make it harder for many migrants living in the U.S. without full legal status to use banking and financial services.

Many immigration opponents see these changes as progress. In a statement following this week’s Supreme Court decisions. A spokesman for the Federation for Immigration Reform said Trump should have full authority to direct who enters the U.S.