Here's what we know about a strong line of storms that crossed central Ohio Monday night into Tuesday morning.

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One death confirmed, other injuries reported

One fatality has been confirmed in Celina, Ohio. Mayor Jeff Hazel say seven people were injured and one 81-year-old man was killed in the storms. He said about 40 houses were heavily damaged.

State of emergency in 3 Ohio counties

Gov. Mike DeWine on Tuesday declared a state of emergency in three Ohio counties — Greene, Mercer and Montgomery.

The emergency proclamation will allow:

State agencies to provide resources and support beyond their normal authority, under the direction of the Ohio Emergency Management Agency.

Department of Administrative Services to suspend state purchasing requirements to support recovery efforts and obtain needed resources such as water and generators more quickly and efficiently.

Where did the tornadoes hit?

Central Ohio was pounded by a strong line of storms Monday evening into Tuesday morning that resulted in widespread damage as it passed.

The National Weather Service issued a tornado watch at around 8 p.m. Monday for a large area of eastern Indiana and central Ohio. Not long after, the first tornado warning was issued in eastern Indiana. A hailstorm of tornado warnings – more than 30 – followed, marching inexorably east, mainly tracking along Interstate 70.

The rapid-fire line of apparent tornadoes tore across Indiana and Ohio overnight, packed so closely together that one crossed the path carved by another.

Multiple tornadoes ripped through eastern Iowa Monday afternoon, damaging several homes, barns and trees.

The storms dropped debris and highway crews had to used snowplows to clear Interstate 75.

Were they tornadoes?

The National Weather Service has confirmed a tornado did touch down in Trotwood during the storms Monday night. Officials said the twister was "at least an EF3 tornado with winds up to 140 mph." Trotwood is a community of about 24,000 people in Montgomery County located northwest of Dayton.

The weather service also confirmed a tornado touched down in Beavercreek during the storms Monday night. Officials said the twister was at least an EF3 tornado. Beavercreek is a community of about 47,000 people in Greene County located southeast of Dayton.

Crews are still assessing damage in other areas to confirm if more tornadoes touched down. There are four assessment teams out in central Ohio. One is in Montgomery County covering areas around Brookville and North Dayton.

A second team is in Greene County in the area of Beavercreek and Xenia. The third team is covering Pickaway and Hocking counties in the areas of Circleville and Tarlton. The last team is in Mercer County working in Celina.

The National Weather Service office at Wilmington said it would be conducting surveys in Celina, New Madison, Laura, Dayton, and Laurelville to determine if there were tornadoes and where they touched down.

What is the damage?

Dayton officials said the city was "hit by a series of devastating tornadoes" overnight and rescue workers are getting their first daylight look at the damage. Dayton Fire Chief Jeffrey Payne said so far there are no fatalities in Dayton and a small number of minor injuries, which he said was "miraculous."

Celina, Ohio, officials said in a statement that the northwest section of the city "sustained significant damage from a tornado" that passed through the community Monday night at about 10 p.m. City officials said there would be updates once damage was assessed.

Urban Search and Rescue teams from Columbus and Cincinnati are among those that will help in today's search efforts.

Thousands without power

Dayton Power and Light reports on its website that more than 50,000 customers are without power following the storms; 41,438 in Montgomery County and 9,354 in Greene County. American Electric Power has reported about 2,400 without power between central and southeastern Ohio. Dayton Power and Light called damage to the Miami Valley “catastrophic,” adding that there are many downed power lines across the region.

That company expects restoring power will take several days.

Dayton's water system is affected, as well. Both of the city's water plants and the system's pumping stations are without power. City Manager Shelley Dickstein said generators were on the way but said there will be a boil advisory for communities served by Dayton Water System.

The power outages have caused a Red Cross shelter at Trotwood High School, where 60 residents were located, to close due to lack of power. The Red Cross said there were more than 135 people in shelters in Dayton, Brookville, Vandalia and Miami County.

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