Myanmar authorities warned Monday against "anarchic acts" after an angry mob killed 10 Muslims and a crowd attacked a police station in a surge in sectarian tensions in the west of the country.
Several hundred people on Sunday set upon a bus in Rakhine state that they believed was carrying those responsible for the recent rape and murder of a local girl, local residents said.
"Nowadays peaceful assembly and peaceful rallies for democracy and human rights are being allowed under the law," an announcement on state television said, confirming the attacks.
"But such an anarchic and unlawful gathering and acts are not permitted. So a necessary investigation will be conducted into this event."
Locals reported increased security in Rakhine state along the Bay of Bengal after the flare-up in unrest in the area, which has a large Muslim minority population including the much-persecuted Rohingya.
Hundreds of people gathered at a police station in the town of Sittwe late Sunday demanding justice because they mistakenly thought a local politician had been kidnapped and killed by Muslims.
"Some drunken people played a leading role. They threw bottles and stones," said Aye Maung, chairman of Rakhine Nationalities Development Party, a political party representing the ethnic Rakhine people.
"The police fired warning shots using rubber bullets. They also used tear gas to disperse the people," he told AFP by telephone, adding that the unrest continued until early Monday.
State media said that a dozen people were hurt and nine detained over that incident.
No arrests have been reported in connection with the killing of the 10 Muslims by a group of ethnic Rakhines -- who are mostly Buddhist -- in Taunggote in Rakhine state earlier on Sunday.
The Burmese Muslim Association said in a statement that eight of the victims were travelling back to Yangon after attending a mosque when they were attacked by a group with knives, while two were from Rakhine state.
"The Rakhines are threatening the Muslims of the other towns of Rakhine state too," it said.
Clashes between Buddhists and Muslims occur periodically in Myanmar and Rakhine state, which borders Bangladesh, is a flashpoint for tensions.
In February 2001, the then-ruling junta declared a curfew in the Rakhine State capital city Sittwe after violent riots broke out between Muslims and Buddhists.
Buddhists make up some 89 percent of the population of Myanmar, with Muslims officially representing four percent.
Pockets of sectarian unrest have occasionally broken out in other parts of the country, where there has been a series of dramatic political reforms since a quasi-civilian regime last year replaced decades of outright military rule.
Rights violations also affect all religious groups in Myanmar, including Buddhist monks who participated in a failed uprising in 2007 and who continue to be arrested and harassed, according to Amnesty International.
Muslim Rohingyas meanwhile are "suppressed and forced to relocate on religious as well as ethnic grounds" while Christian religious sites are relocated or destroyed, it said in its annual report released last month.