High gas prices have more people getting out of their cars and onto trains and buses.

According to industry figures, ridership on mass transit surged by more than 5 percent during the second quarter of the year. That means 2.8 billion trips were made on the nation's subways, buses, commuter railroads and light-rail systems.

"Record numbers of Americans from small communities to large cities continue to ride public transportation to beat the high gas prices," said American Public Transportation Association President William W. Millar. "This large quarterly increase is remarkable, particularly since an economic downturn usually causes fewer people to ride public transit."

Light rail had the highest percentage of ridership increase among all modes, with a double digit 12.3 percent increase for the second quarter. Bus ridership saw the second highest increase with a 5.1 percent nationwide, followed by commuter rail at 4.9 percent and heavy rail at 4.3 percent.

But that surge in riders is also straining agencies that can't afford to expand service and are struggling to maintain the services they already offer.

Transit advocates said more federal support is needed. The House has passed a bill to make $1.7 billion available to transit agencies over the next two years.

"This surge in ridership underlines the urgent need for increased investment in public transportation from state, local and federal governments," Millar said.

A Senate committee will hear from transit officials Tuesday.