Competition between newly-successful companies, combined with online ticket sales, significantly reduced fares by 2002. Fares were reduced by 400 percent during some price wars, and a number of operators advertised $10 fares. This led to gang violence in which rival bus operators killed or injured each other. Because of their low fares, Chinatown bus lines had very low profit margins; some, like YO! Bus, went bankrupt and ceased operations. However, the Chinatown bus sector made up an increasing number of trips within the northeastern U.S.