Many Argentines armed and barricaded themselves in their homes and stores in fear of looting mobs Tuesday as the nation's celebration of 30 years of uninterrupted democracy was marred by police strikes for higher pay.

Politicians struggled to assert their authority over security forces even as they agreed to salary increases so steep that many provinces won't be able to pay their debts at month's end.

President Cristina Fernandez sought to contain the crisis Tuesday night, charging that antidemocratic elements were trying to undo Argentina's hard-won gains. "We must condemn the extortion of those who carry arms to defend society," she declared.

The speech was her first response to a weeklong series of provincial police strikes. - AP