The Immigration and Naturalization Service is considering raising its fees, prompting criticism from immigrant groups who say would-be citizens and foreign workers should not be penalized for the agency's mismanagement, the Associated Press reported. Bob Gardner, INS assistant commissioner for budget, said the agency is looking for ways to cover rising costs. He would not say what fees could go up or by how much, and emphasized the increases are only under consideration. The INS budget for completing applications and naturalization programs comes largely from applicants' fees. The agency's budget has nearly quadrupled since 1994 to $500 million, and the staff has more than doubled to about 6,100. But during the same time, the INS backlog on processing applications increased nearly fourfold to about 3.9 million, according to a report by the General Accounting Office issued earlier this month. INS raised 30 of 40 fees in 1998 and 1999.