A fourth firefighter has died from burns after he and several colleagues were overcome by a fast-moving wildfire near the Colorado-Utah border last month, officials said Saturday.

Nathan Matthews, 43, died Friday, the federal Interior Department said in a release. He was from Lincoln, Nebraska.

“This is another heartbreaking loss for our wildland fire family,” said U.S. Wildland Fire Service Chief Brian Fennessy.

Matthews’ death came nearly a month after he and other firefighters were enveloped June 27 in what’s known as a burnover — a situation in which a fire spreads and closes off all escape routes. They were part of a Helitack crew — a group that gets dropped by helicopter into remote areas to try to squelch new, rapidly expanding fires — that had been deployed in Mesa County, Colorado, west of the city of Grand Junction.

The firefighters deployed tent-like emergency shelters to try to shield themselves from the flames, officials said, but three firefighters died at the scene: Emily Barker, 38; Nick Hutcherson, 27; and Sydney Watson, 26.

Matthews and another were taken for medical treatment. The Interior Department declined Saturday to discuss their treatment, Matthews’ career or the surviving firefighter’s current condition.

Watson, Hutcherson and Barker were honored at a memorial service earlier this month. Memorial arrangements for Matthews haven’t yet been announced.

The western U.S. has been contending with dozens of large fires this summer. Months of dry weather, a record lack of snow in some areas, hot spells and erratic winds have contributed to the blazes.

Firefighters were bracing Saturday for the possibility of worsening fires in Oregon, where a blaze near Bend was of particular concern because of its proximity to people.