A rapid-fire line of apparent tornadoes tore across Indiana and Ohio overnight, packed so closely together that one crossed the path carved by another.
The storms strew debris so thick that at one point, highway crews had to use snowplows to clear an interstate.
At least half a dozen communities from eastern Indiana through central Ohio suffered damage, according to the National Weather Service, though authorities working through the night had reported no fatalities as of early Tuesday.
The National Weather Service said more than 70,000 power outages were affecting 5 million people across the state. That figure was based on the population of where those outages occurred, NWS meteorologist John Franks told NBC News. The website PowerOutage.us reported that around 68,000 customers remained without electricity at 6:10 a.m.
The response would require a “multi-day restoration effort,” utility Dayton Power & Light said in an early morning tweet. The company said 64,000 of its customers alone were without power.
The city of Dayton urged residents to conserve water after the storms cut power to water plants and pump stations. Multiple schools in the area were closed or had delayed starts Tuesday.
Towns just outside Dayton, Ohio, took some of the heaviest hits. The National Weather Service tweeted Monday night that a “large and dangerous tornado” hit near Trotwood, Ohio, 8 miles (12 kilometers) northwest of Dayton. Several apartment buildings were damaged or destroyed.
Just before midnight, not 40 minutes after that tornado cut through, the weather service tweeted that another one was traversing its path, churning up debris densely enough to be seen on radar.
The aftermath left some lanes of Interstate 75 blocked north of Dayton. Trucks with plows were scraping tree branches and rubble to the side to get the major north-south route reopened, according to Matt Bruning, a spokesman for the Ohio Department of Transportation.
Trying to clear the debris in the middle of the night is a difficult task, complicated by darkness and downed power lines, Bruning said.
“We’ll do a more thorough cleaning after we get lanes opened,” he told The Associated Press by text early Tuesday, noting that tow trucks would have to haul off damaged vehicles along the roadway, too.
In Brookville, west of Dayton, the storm tore roofs off schools, destroyed a barn and heavily damaged houses.
Crews were also clearing debris in two other counties northwest of Dayton.
In Montgomery County, which includes Dayton, Sheriff Rob Streck said many roads were impassable. The Montgomery County sheriff’s office initially said the Northridge High School gymnasium would serve as an emergency shelter in Dayton but later said it wasn’t useable.
In Indiana, at least 75 homes were damaged in Pendleton and the nearby community of Huntsville, said Madison County Emergency Management spokesman Todd Harmeson. No serious injuries were reported in the area or other parts of the state.
Madison County authorities said roads in Pendleton, about 35 miles (56 kilometers) northeast of Indianapolis, are blocked with trees, downed power lines and utility poles. Pendleton High School is open as a shelter.
The National Weather Service said a survey team will investigate damage in Madison County and possibly in Henry County. Another team may survey damage in Tippecanoe County.
Associated Press writer David Runk contributed to this report.