SPRINGFIELD - Illinois Attorney General Lisa Madigan's office is looking into whether rising gas prices across the state are a result of Hurricane Ike, or gas gouging by station owners.

"We are aware of reports of gas price increases in many parts of Illinois, and with Hurricane Ike's approach, we have investigators in the field monitoring these increases," said Madigan spokeswoman Robyn Ziegler.

Those investigators will try to determine whether the rising cost of gas is a legitimate result of the market or an unfair attempt by gas stations to make money off of the incoming hurricane, Ziegler said.

Anyone who suspects a gas station may be gouging customers can call the office at (800) 243-0618 in Springfield or (800) 243-0607 in Carbondale.

Southern Illinois residents on Thursday night and Friday saw a rise in gas prices, but the severity of the increase depended on location.

Prices at most stations ranged between $3.99 per gallon area to $4.09 per gallon. However, some stations posted prices as high as $4.75 for regular unleaded.

In Benton and West City, prices were as low as $3.66 and as high as $4.15. Prices shot from about $3.68 Thursday to $4.10 Friday.

In Marion, prices ranged from $3.69 to $4.09.

In Saline County, however, Russell Oil Co. was charging $4.75 per gallon of regular unleaded, compared to competitors peaking at $3.99 in Eldorado and $4.09 in Harrisburg.

Employees at Russell said they were instructed not to answer questions, and the owner did not return calls for comment.

Bill Culkin of Harrisburg said he reported the prices to the attorney general's office.

Culkin, who works as a truck driver, said he was surprised by the prices, especially after seeing gas costs outside of the state earlier in the day. He said in Mount Vernon, Ind., prices were $3.89.

According to the American Automobile Association's Web site, the state average in Illinois Friday was $3.932.

Residents of Alaska and Hawaii have the highest prices at $4.393 and $4.326, respectively.

Texas, the heart of oil refining in the U.S. and now facing Hurricane Ike, averages $3.546.

The national average is $3.675.

Natalie Bauer of the attorney general's office said there have been numerous complaints of price gouging.

"We encourage consumers to report suspected price increases during the hurricane to the attorney general's consumer fraud hotline," Bauer said.

U.S. Senator Dick Durbin, a Democrat from Springfield, said oil companies are making a nice profit off of the American people with crude oil prices dropping by 40 percent the last six weeks while gasoline and diesel fuels remain high.

"The price gouging going on here is awful," Durbin said.

- John Homan, Becky Malkovich and The Southern's Springfield bureau contributed to this story.

codell.rodriguez@thesouthern.com

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