More than 20 people have been killed in western Burma's Rakhine State, as international pressure mounts for an end to the sectarian fighting between ethnic-Rakhine Buddhists and Rohingya Muslims.

President Thein Sein has declared a state of emergency and has sent army troops to Rakhine, which has been hit with a wave of rioting and arson in recent days. Hundreds of homes have been destroyed.

There was a heavy security presence Tuesday in the regional capital, Sittwe, where fires dotted the area amid destroyed homes and shops, and people ran to escape the chaos. In Maungdaw, residents reported mostly peaceful streets, and 400 kilometers away in Rangoon, police dispersed a small mob of monks.

In predominately Muslim Bangladesh, officials said their border guards have turned back more than 500 Rohingya Muslimstrying to flee the fighting. Bangladesh's Foreign Ministry said it is not in the the country's best interest to allow the Rohingyas entry.

The United States has expressed concern about the situation. Secretary of State Hillary Clinton said the violence underscores the need to make a serious effort to achieve national reconciliation in Burma.

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Troops Patrol Western Burma as Sectarian Strife Continues

Violence Erupts

The violence erupted a week ago when a Buddhist mob in Sittwe ambushed a bus and killed 10 Rohingya passengers, mistakenly believing they were responsible for the recent gang-rape and murder of a Buddhist woman.

According to an official with U.S.-based Human Rights Watch, Phil Robertson, there are reports that riot police in the region are favoring the ethnic Rakhine over the Rohingya. He said the government must