Wildfires were spreading rapidly in Texas and Oklahoma on Tuesday evening, prompting evacuations and the closure of a plant that disassembles nuclear weapons.

In Texas, Gov. Greg Abbott issued a disaster declaration on Tuesday for 60 counties, activating state resources to help the local firefighters battling the wildfires.

The largest current blaze in the Texas Panhandle, the Smokehouse Creek fire, has burned at least 250,000 acres since igniting on Monday, fueled by strong winds and dry conditions, according to the Texas A&M Forest Service. The fire remained uncontrolled Tuesday evening.

A hospital system in Canadian, Texas, about 100 miles northeast of Amarillo, evacuated all of its patients and staff Tuesday afternoon, according to the Hemphill County Hospital District. In Fritch, Texas, the Moore County Sheriff’s Office told residents of several neighborhoods to evacuate.

In Oklahoma, some residents of Ellis and Roger Mills counties, near the state’s western border with Texas, were told to leave, said Levi Blackketter, the director of Roger Mills County Emergency Management, in a statement.

“Hot and dry conditions caused by high temperatures and windy conditions are expected to continue in the region in the coming days,” Governor Abbott said in a statement. “These conditions could increase the potential for these wildfires to grow larger and more dangerous.”

Near Amarillo, Texas, a wildfire was burning north of Pantex, a plant that disassembles nuclear weapons, officials said. The plant paused operations and ordered nonessential personnel to evacuate.

There was no fire on the plant’s site or near its boundaries, but nuclear safety officials were responding, said Laef Pendergraft, a nuclear safety engineer for the National Nuclear Security Administration production office at Pantex. The plant has an on-site fire department, he said, speaking at a news conference.

This is a developing story.