CNN
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At least six people were injured as severe thunderstorms swept through parts of Oklahoma early Sunday and tornadoes and flooding were reported overnight, authorities said.

The six injured people were taken to the hospital with non-life-threatening injuries, said Valerie Littlejohn, Oklahoma City police public information officer.

Several structures were also damaged in the area, as well as power lines, trees, gas lines, traffic signals and road signs, she said.

Video from CNN affiliate KOCO shows the damage, with cars overturned and entire homes destroyed. The storms toppled telephone poles and snapped trees in half. Debris is scattered across affected areas, including large pieces of wood and metal from destroyed buildings.

About 95,000 customers in Oklahoma were without power Sunday morning, according to poweroutage.us.

Tornadoes were reported east of Oklahoma City, and tornado and thunderstorm warnings are in effect in the Oklahoma City area, the National Weather Service said.

“Folks, don't let your guard down too much – we're already seeing the atmosphere recover ahead of another round of thunderstorms, heavy rains, flooding and possible severe weather today,” the weather service said in a post on X .

The Oklahoma Department of Emergency Management said it was monitoring the severe weather.

Flooding on Interstate 35 closed all but one northbound lanes near Forest Park in the Oklahoma City area, the Oklahoma Department of Transportation said.

According to Scott Douglas, the department's public information officer, the Oklahoma City Fire Department responded to several vehicles that were flooded due to heavy rains.

At around 1:20 a.m. local time, the weather service warned that a severe thunderstorm with a tornado was moving through east Oklahoma City toward Midwest City and Tinker Air Force Base. A tornado warning was issued for over 300,000 people in Moore, Midwest City and Del City.

The University of Oklahoma urged students and staff on its Norman campus to “Seek shelter in the building you are in NOW. Go to the lowest floor/interior.”

Research shows that nighttime tornadoes are more than twice as deadly as daytime tornadoes. Nighttime tornadoes are difficult to spot in the dark, and people sleeping may not be aware that danger is imminent.

Concern about this week's tornado threat is heightened considering how productive the year has been for twisters in the United States. The number of tornadoes reported so far this year is the second highest on record, trailing only the 2,156 in 2011.

Severe thunderstorms occur most often in the spring and summer, but a second wave of dangerous storms and tornadoes occurs in the fall and winter as cold air from the north often collides with warmer, moist air from the Gulf of Mexico.