Flags at U.S. embassies across the globe fly at half-mast.

Staff are marking the death of the U.S. envoy to Libya and three of his staff.

The were killed in an attack on their consulate in Benghazi.

Violent protests at U.S. embassies across the Middle East have spread after a video clip -- linked to a U.S. made film -- was released online.

It depicts the Prophet Mohammad as a fraud and philanderer.

In Beijing police were out in force around the U.S. embassy.

Seoul's U.S. embassy hoisted its national flag at half mast, but authorities have not beefed up security there, according to an embassy official.

Several police were stationed outside of the embassy in Jakarta, amid the tightened security measures there.

A Jakarta motorcycle taxi driver expressed his condolences for the attacks.

But another said the U.S. should have anticipated an attack after the video clip was released.

Violent protests have continued through the day in Egypt and Yemen.