Port-au-Prince, Haiti ? U.N. peacekeepers used rubber bullets and tear gas to chase away hungry Haitians who stormed the presidential palace Tuesday demanding the resignation of President Rene Preval. The riots over soaring food prices turned into looting as terrified residents huddled inside.

The protesters tried to break into the presidential palace Tuesday morning by charging its chained gates with a rolling Dumpster, demanding Preval step down.

“We are hungry! He must go!” they cried.

Preval, backed by Washington, was inside the palace at the time, aides said. He has made no public statements since the riots began last week.

Brazilian soldiers in U.N. helmets forced the protesters away from the palace gates. But as the protests turned into looting, the outnumbered peacekeepers only watched as people broke into shops around the palace.

After dark, the looting spread. People broke into stores and factories on a road to the airport, witnesses said, amid blackouts reported from Port-au-Prince’s center up through its densely populated hills. Frightened residents barricaded themselves behind locked doors.

The U.S. Embassy suspended routine operations today because of the violence, and advised Americans in Port-au-Prince and Les Cayes to remain indoors. Embassy buildings were pelted with rocks Tuesday but there were no reports of injuries to U.S. citizens.

Food prices, which have risen 40 percent on average since mid-2007, are causing unrest around the world. But nowhere do they pose a greater threat to democracy than in Haiti, one of the world’s poorest countries.

For months, Haitians have compared their hunger pains to “eating Clorox” because of the burning feeling in their stomachs. The most desperate depend on a traditional hunger palliative of cookies made of dirt, vegetable oil and salt.