At least seven people were injured after severe storms spawned several tornadoes across northeastern Oklahoma Wednesday night, authorities said.

The City of Tulsa said in a statement that several roads were closed and police and fire crews were scouring the city. In one damaged area, they were searching every home, but there were no immediate reports of anyone missing, city public information officer Michelle Allen. The Streets and Water Departments are assisting with road barricades and debris removal.

National Weather Service meteorologist Amy Jankowski said a tornado touched down and lifted up numerous times as it roared through the Tulsa and Owasso areas. She added that the weather service received multiple reports of lofted debris, trees down and some structural damage.

Emergency Medical Services Authority spokeswoman Kelli Bruer said the ambulance service transported seven patients and at least one of them was in critical condition. Six others were listed in serious condition.

Tulsa fire officials told Fox 23 News that there was at least one-square mile of damage. They also said roofs in several neighborhoods were damaged and that a gun club was leveled by the storms.

Nearly 9 million people in parts of Texas, Oklahoma, Louisiana and Arkansas were in an enhanced area of risk Wednesday, putting them in the bull’s-eye for some of the strongest storms, the national Storm Prediction Center said earlier Wednesday. The area of highest risk included the Dallas-Fort Worth metropolitan area.

In Louisiana, the National Weather Service issued a flash-flood watch for northern parts of the state until 7 p.m. Thursday. Forecasters say multiple rounds of strong to severe thunderstorms will produce 2 to 4 inches of rain, and perhaps 6 inches in some parts of the state.

“Heavy rain from waves of storms could renew flooding over north Louisiana,” said Cynthia Palmer, a forecaster at the weather service’s office in Shreveport, Louisiana.

The ground remains saturated in that part of the state, which saw record flooding earlier this month, Palmer said.

“We will see the heaviest rain in the Monroe area of northeast Louisiana starting late this afternoon and evening and another wave on Thursday,” Palmer said Wednesday morning. “This is the area that could see up to 6 inches.”

Forecasters in northern Mississippi said thunderstorms would bring about 2 to 4 inches of rainfall. A flash-flood watch was in effect until Thursday evening.

Alabama forecasters said the strong storms may develop tornadoes Thursday with winds up to 70 mph, quarter-sized hail and heavy rains.

In Georgia, forecasters said more than 4 inches of rain could fall in western parts of the state.

The possibility of additional tornadoes remained from the storms that hit Oklahoma, Jankowski said. She said that while the system wasn’t as strong as when it passed through the Tulsa area, it still has the structure to produce tornadoes.

The Associated Press contributed to this report.