The death toll from a tornado in the US has risen to at least seven after storms unleashed a "war zone" of destruction in north-west Ohio.
The tornado destroyed dozens of homes and an emergency services building, and collapsed a cinema roof in Illinois and ripped siding off a building at a Michigan nuclear plant, forcing a shutdown.
But the worst was largely reserved for a seven-mile strip south east 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 several hours before the graduation ceremony was supposed to begin.
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," Mr ummer said. "It's pretty disheartening."
Rescue officials are still searching homes and could not say whether anyone else was missing, Fire Chief Todd Walters said.
Those killed included a person outside the police department and a motorist, Mr 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 south east of Toledo. He said two other people died at hospitals but he did not have details.
More than 30 people in the Toledo area were taken to hospital. Two adults and two children were in critical condition, said Mercy Hospital system spokeswoman Gloria Enk.
In south-eastern 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 and the plant is expected to go back into operation, Mr Smith said.
Tornadoes also were reported in Illinois, Michigan and Indiana.