There's a gas price war in North Charleston. The battleground: Rivers Avenue at Otranto Road.

On Thursday, two service stations there drove the cost of a gallon of unleaded regular down to $2.19.

The competition began Tuesday morning between Murphy Express and Circle K. "They dropped their price and we dropped our price to match them," said Tim Hopkins, Murphy Express store manager.

"We're not going to raise our prices first. When they raise theirs, we'll raise ours back," Hopkins said.

He predicted the extra-low prices will continue at least through the week. Business on Thursday was triple what it was a week ago because of the cheap gas. It was expected to be the second-busiest day in company history, Hopkins said.

The rush of customers at both stores created gridlock as drivers formed lines at the pumps up to 10 cars deep. "It's basically a parking lot out there," Hopkins said.

Murphy Express is pricing gas about 2 cents below cost to win the campaign for customers, he said.

"I wanted to go to Murphy's, but there was a huge line," said Caroline Bolles, who was buying gas at the nearby Raceway for $2.29 per gallon.

"I wish gas prices were lower everywhere," said Ray Robinson of Ladson, who was pumping gas at Murphy Express.

Scott Campbell said he went to Murphy Express for cigarettes, but the cheap gas caught his eye. "I had no choice but to jump in line," he said.

"I think it should stay there or go down even lower," Dorothy Craven said while topping off her tank at Murphy Express.

Michelle Whittaker of Alvin said she drives 80 miles round-trip four days per week to attend Trident Technical College. She was buying gas at Circle K. "My husband is the only one working, and I have three kids. It's a real tight budget," Whittaker said.

She planned to bring two other family cars to fill up at Circle K.

A Circle K employee referred questions to the corporate office, which did not immediately return a call for comment.

The statewide average for regular unleaded on Thursday was $2.45 per gallon. Brendan Byrnes, public relations manager for AAA Carolinas, said that convenience stores use gasoline sales to snag customers who buy snacks, drinks and other items. "That's where they make a much larger profit margin than on gas," he said.

On Thursday, the Exxon at Rivers and McMillan avenues was selling regular gas for $2.46 per gallon. In Charleston, the Shell station at Huger and King streets offered $2.49 per gallon for unleaded regular.

Reach Prentiss Findlay at pfindlay@postandcourier.com or 937-5711.