OKLAHOMA CITY - Gas prices across Oklahoma are up sharply during the past week, rising 20 cents per gallon.
AAA Oklahoma reports the average price for a gallon of self-serve regular on Tuesday is $3.58 compared to $3.38 a week ago.
AAA spokesman Chuck Mai says the reason for the spike is difficult to pinpoint.
Mai says rising prices for crude oil and tight gas supplies don't fully explain the increase and AAA is "puzzled" somewhat by the price.
Prices in selected cities range from $3.40 per gallon in Idabel to $3.63 per gallon in Stillwater.
Oklahoma City motorists were paying an average of $3.61 per gallon while Tulsans were paying $3.52.
The national average is $3.58 per gallon.
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