HUNDREDS of Buddhists have threatened to kill Muslims as they rode on motorcycles through Burma's second-largest city of Mandalay, raising the prospect of further communal violence after two people died in unrest earlier in the week.

Inter-religious violence has flared throughout the country over the past two years, threatening to undermine political reforms initiated by the quasi-civilian government of President Thein Sein, which took office in 2011 following 49 years of repressive military rule.

At least 240 people have been killed and more than 140,000 displaced since June 2012.

Most of the victims have been members of Burma's Muslim minority, estimated to be about five per cent of the population.

Around 300 Buddhists were riding around Mandalay yesterday, many of them wielding knives, clubs and bamboo poles.