TULSA, Okla. (AP) - A possible tornado struck near midtown Tulsa, injuring more than a dozen people and causing power outages and roof damage to businesses.

No deaths are reported following storms that struck shortly after 1 a.m. Sunday.

City of Tulsa spokeswoman Kim Meloy said at least 13 people were taken to hospitals in undisclosed condition.

The storm also damaged power poles and more than 11,000 customers were without power at one point. More than 9,000 remained without electricity Sunday morning.

National Weather Service meteorologist Amy Jankowski said preliminary reports indicate a tornado, but it could be Monday before surveyors complete their investigation and there is no preliminary estimate of the storm's strength.

Jankowski said tornadoes are generally associated with spring months and said an August tornado is uncommon, but not "outrageously rare."

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