MILLBURY, Ohio – A tornado unleashed a “war zone” of destruction in northwest Ohio, destroying dozens of homes as storms killed at least seven people and threatened to do more damage Sunday when they hit the Northeast.

Storms collapsed a movie-theater roof in Illinois and ripped siding off a building at a Michigan nuclear plant, forcing a shutdown.

But the worst was reserved for a 100-yard-wide, 7-mile-long strip southeast of Toledo now littered with wrecked vehicles, splintered wood and family possessions.

The tornado ripped the roof and back wall off Lake High School’s gymnasium about 11 p.m. Saturday, several hours before the graduation ceremony was supposed to begin there. The school board president said one of the victims was the father of the class valedictorian.

Two buses were tossed on their sides and another was thrown about 50 yards, landing on its top near the high school’s football field.

Lake Township Police Chief Mark Hummer flew over the damaged area and said at least 50 homes were destroyed and another 50 severely damaged, as well as six commercial buildings. The storm fell over an area of farm fields and light industry, narrowly missing the heavily populated suburbs on the southern edge of Toledo. “It’s a war zone,” he said. “It’s pretty disheartening.”

Hummer said Sunday that all buildings had been searched and everyone was accounted for. Rescuers were searching a wooded area and a field near the worst hit portion of town as a precaution.

The tornado turned a police and emergency medical services building into a mishmash of 2-by-4 framing and pink insulation.

The storm ripped off most of the building’s back half and wrapped part of the metal roof around a tree. At least six police vehicles were destroyed.

The storm knocked out emergency services for a short time, and all the emergency dispatchers and 911 operators had to be moved to a nearby town.

“When the people who are supposed to help you are victims of the storm, it does take you a minute to catch your breath,” Hummer said.

Those killed included a person outside the police department and a motorist, Hummer said. He said a young child and two other victims were from nearby Millbury, a bedroom community of roughly 1,200 about 10 miles southeast of Toledo. Hummer said two other people died at hospitals.

One of the victims was the father of Lake High School’s valedictorian, said Tim Krugh, president of the school district’s board. Krugh said the school has rescheduled graduation for Tuesday evening at a Toledo community college.

Neighbors said the house of the valedictorian’s family was destroyed, and all that was left was a basement filled with water.

More than 30 people in the Toledo area were hospitalized, including two adults and two children in critical condition, Mercy hospital system spokeswoman Gloria Enk said.

In southeastern Michigan, severe storms and high winds ripped siding off a building at the Fermi 2 nuclear plant, causing it to shut down automatically, said Dan Smith, the public information officer for Monroe County. Investigators were inspecting the nuclear plant on the shore of Lake Erie on Sunday, and the plant was expected to go back into operation, Smith said.

About 35,000 people were without power but it wasn’t clear whether that was directly related to the nuclear plant’s shutdown or because of damage to power lines in the area, Smith said.

Eleven people with minor injuries were taken to hospitals from Dundee, Mich., where a tornado touched down with winds of about 130 mph.

Tornadoes also were reported in Illinois. More than a dozen people were injured in Dwight, Ill., where about 40 mobile homes and 10 other homes were destroyed, Illinois Emergency Management Agency spokeswoman Patti Thompson said.

A cold front colliding with warm unstable air produced the storms that struck Saturday night, meteorologist Marty Mullen of the National Weather Service said, and that front was draped from New England south through the mid-Atlantic region later Sunday. The storm was weakening as it headed east.