TIJUANA, Mexico  —  Rising gas prices are leading U.S. motorists to flock to fuel pumps south of the border for savings of 25 percent or more, the Los Angeles Times reported.

The Mexican government has been capping retail prices at the state-owned petroleum company Pemex due to inflation concerns. While drivers in California are paying an average of $3.43 a gallon, regular-grade gasoline just across the border in Tijuana is selling for about $2.60 a gallon.

Roger Moore, a 63-year-old management consultant who owns a second home in the Mexican state of Baja California has made a point of stopping at a station here this week to top off the tank of his Ford minivan before heading back to West Hollywood, Calif.

"It costs $65 for a tank of gas up there, and it costs me $45 here," he told the Times. "It's a monopoly, and it's cheaper."

Mexican station owners are pumped by the surge in business, too. Although they say few Americans are traveling to Mexico specifically to fill their tanks, many more than usual are taking advantage of the chance to buy cheap gas when they cross the border to work or play. They are also seeing increased sales to Mexican residents who work in the U.S.

Outlets along the nearly 2,000-mile border are serving more cars with U.S. plates. The jump is reflected in Pemex's pump sales, up 10.5 percent through the first four months of the year compared with the same period last year. Vendors are girding for a rush of business Memorial Day weekend as Americans head to their Mexican vacation homes and take home a cheap souvenir in their tanks.

"This has been very, very favorable for us," said Jorge Farfan Gonzalez, general manager of a franchisee that operates 17 Pemex outlets in Baja.

But some say that low-cost gas might not be such a bargain. Mexican stations are notorious for dispensing short liters. And their fuel isn't as clean as that mandated in California.

That's tough on the environment, and it could harm your vehicle too, said Rich Kassel, a clean fuel expert with the Natural Resources Defense Council in New York. Mexico's regular gasoline is loaded with sulfur. Kassel said frequent fill-ups could wreak havoc on the catalytic converters of the newest cars and trucks sold in the U.S.