Unstable gasoline prices and mounting environmental concerns are fueling increasing sales of new hybrid vehicles, according to the Columbus Dispatch. Hybrids, which combine a gasoline engine with an electric motor to improve mileage, had the best month of U.S. sales ever in February with 4,410 cars -- led by a 35 percent increase in sales of Honda's Civic Hybrid, the Dispatch said. Hybrid sales have remained strong in March, automakers said. Officials at Honda and Toyota, which make the only hybrids on the market today -- Civic, Honda Insight and Toyota Prius -- aren't ready to declare a trend just yet. U.S. hybrid sales of 36,000 vehicles last year accounted for just 2 percent of all 16.8 million vehicles sold. But with the recent surge in sales, and with Toyota, Ford and General Motors all introducing models soon -- including hybrid versions of the sport-utility Ford Escape and Lexus RX330 -- hybrids are becoming more mainstream, according to Michael Flynn, director of the Office for the Study of Automotive Transportation. And if gasoline prices continue to spike, more consumers will take a closer look, central Ohio dealers say, according to the Dispatch.