NORTHWOOD, N.D. – A tornado destroyed two mobile home parks, killing one person, and blew out windows in homes and buildings across the town, officials said Monday. At least 18 people were injured.

“This town is a mess. This town is a disaster,” said Kevin Dean, a spokesman for the town’s emergency operations center. “There’s virtually nothing … that hasn’t been damaged.”

The roof was torn off the town’s school and water was inside the classrooms. Monday was supposed to be the first day of classes for the school year, but classes were canceled for the week.

Residents of the town’s health center, which includes a small hospital and a 77-bed nursing home, were moved into corridors before the storm struck and none was injured, nursing director Carla Sletten said. Windows were broken on one side of the nursing home, she said.

Gov. John Hoeven issued an emergency declaration Monday and sent the National Guard to help with cleanup.

Wreckage and fallen power lines blocked some streets after the twister struck Sunday night. Electricity was cut off to the entire city as a precaution. Generators were set up for the health center, and the school was closed Monday.

National Weather Service meteorologist Greg Gust estimated the twister’s wind hit 170 mph, and said it was nearly a mile wide when it hit the town.

Grand Forks County Sheriff Dan Hill said the extent of damage “just floored me.”

“There were cars that looked like they went through a crusher,” he said.

The tornado demolished two neighboring trailer parks on Northwood’s north side, which had 19 units in all, and killed Larry Weisz, 57, who was pinned between the base of a mobile home and a tree, Grand Forks County Sheriff Dan Hill said.

The injuries of 18 others were not considered life-threatening, officials said.

“To me, it doesn’t look like there’s anything salvageable,” said Rick McDonald, owner of the parks.

Russell and Verna Melfald huddled in a corner of their mobile home and prayed when the tornado struck.

“We were crying,” Russell Melfald said in tears. “We thought we were going to go.”

Bonnie Fisher was visiting a friend in one of the mobile home parks when the tornado struck.

“We heard the sound, which was just like a roaring train, and just as we were trying to get out, the lights went out, the windows shattered and the next thing we knew, we were down, and the trailer was on top of us,” Fisher said.

Northwood, 30 miles southwest of Grand Forks, has about 950 residents.

Forecasters said North Dakota could get more severe weather Monday, due to a mass of warm, unstable air followed by a strong cold front.