Myanmar declared martial law in four central townships on Friday after unrest between Buddhists and Muslims stoked fears that last year's sectarian bloodshed was spreading into the country's heartland in a test of Asia's newest democracy.
Whole neighbourhoods were still smouldering on Friday and agitated Buddhist crowds roamed the streets after three days of turbulence, said Reuters reporters in the city 540 km north of commercial capital Yangon.
State television said President Thein Sein had declared a state of emergency and imposed martial law in the four districts, placing the military, rather than local police, in charge of security. Authorities imposed an overnight curfew on Wednesday.
Twenty people, including a Buddhist monk, have been killed and dozens wounded since Wednesday, said Win Htein, a lawmaker for the opposition National League for Democracy (NLD) party.
Two camps now held more than 2,000 people displaced by the fighting, he added.
The unleashing of ethnic hatred, suppressed during 49 years of military rule that ended in March 2011, is challenging the reformist government of one of Asia's most ethnically diverse countries.
"I am really sad over what happened here because this is not just happening to one person. It's affecting all of us," said Maung Maung, a Buddhist official in Meikhtila.
The unrest is a reprise of last year's violence in Rakhine State in western Myanmar, which officially killed 110 people and left 120,000 homeless, most of them stateless Rohingya Muslims.