WASHINGTON—Two companies that provide workers for the State Department say they fired or otherwise punished those who improperly accessed the passport records of the three major presidential candidates. The security breaches touched off demands for a congressional investigation.

“None of us wants to have a circumstance in which any American’s passport file is looked at in an unauthorized way,” said Secretary of State Condoleezza Rice as she offered apologies to the candidates.

Stanley Inc., based in Arlington, Va., and The Analysis Corp., or TAC, of McLean, Va., said Friday that their employees’ actions were unauthorized and not consistent with company policies.

Stanley said it fired two subcontractors involved in accessing the files of Sen. Barack Obama when their actions were discovered. A separate search showed that workers also had snooped on Sens. John McCain and Hillary Rodham Clinton, State Department spokesman Sean McCormack said.

TAC said it had been notified earlier in the day that one of its contractors had acted improperly—in this case, according to the State Department, by accessing Obama’s records. TAC decided to honor a State Department request to delay firing the consultant to give investigators time to conduct its investigation, the company said.