Story highlights One person was taken to a hospital and is in critical condition

Tweet warning sent out: "Take cover immediately!"

(CNN) The blare of tornado sirens filled the Oklahoma night Wednesday as at least one tornado struck the state, according to the National Weather Service office in Tulsa.

Seven patients were taken to hospitals in the greater Tulsa area, Laura O'Leary with the Oklahoma Emergency Medical Services Authority told CNN.

One person was in critical condition, she said.

TORNADO NORTH OF AIRPORT pic.twitter.com/tHZJT39een — Brandyn (@BAK_yn) March 31, 2016

"Likely tornado on the ground between 66 and I-44 between Verdigris, Claremore moving ENE. Take cover immediately!" the agency tweeted

The powerful storm was moving east at 25 mph and produced hail up to 1.75 inches in diameter.

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