The U.S. State Department issued a worldwide travel alert following President Barack Obama's announcement late Sunday of the assassination of al-Qaeda leader Osama bin Laden.
"Given the uncertainty and volatility of the current situation, U.S. citizens in areas where recent events could cause anti-American violence are strongly urged to limit their travel outside of their homes and hotels and to avoid mass gatherings and demonstrations," the alert stated.
State Department officials warned U.S. embassies of the "enhanced potential for anti-American violence given recent counterterrorism activity in Pakistan."
Embassy staff was urged to maintain heightened security measures against potential backlash by terror groups.
Officials noted that some embassies and consulates may close temporarily or suspend public services if the "evolving security situation" warrants such action.
-- The Associated Press contributed to this report.