Long-standing tension between the ethnic Buddhist Rakhine majority and the Muslim Rohingya minority in the West of Myanmar continues.
On Friday six towns were hit by clashes. A night-time curfew is in place in several locations including Min Bya and Mrauk Oo where the latest spate of violence began.
The Myanmar government estimates that 28,000 people have been displaced in Rakhine state since the latest violence started on 21 October. More than 100,000 have been forced to flee in total since clashes began in June.
Earlier, the government acknowledged more than 80 people had been killed and whole villages destroyed in violence between ethnic Rakhine Buddhists and Muslim Rohingyas.
UN officials who joined a government tour said many of the displaced needed urgent aid.
It is unclear what prompted the latest clashes. The Rakhine Buddhists and Rohingya Muslims both blame each other for the violence. However, there is widespread public hostility towards the Rohingya- regarded as illegal immigrants by the Myanmar authorities, despite having lived in the country for decades.
The UN has warned that Myanmar’s reform programme could be put at risk by continued communal violence in Rakhine. A UN team was allowed to accompany government officials on a tour of the affected areas of Rakhine state on Saturday.
The UN's Myanmar humanitarian chief, Ashok Nigam, said that while government had given estimates of 22,587 people displaced in the latest wave of violence, there could still be "additional numbers".
Getting aid to the displaced would be a major challenge, Mr Nigam said, adding that 21,700 of them were Muslims."The situation is certainly very grave and we are working with the government to provide urgent aid to these people," he said.Groups campaigning for the rights of Rohingyas say some of those who fled by boat have died at sea.
On Saturday, President Thein Sein acknowledged mass destruction in the region, with whole villages and more than 4,600 houses burnt, and announced tighter security. In one district, some 3,000 with burnt out poles from the houses and charred stubs of trees was all there was to see.
The BBC's Jonathan Head in Bangkok says the government has declared a curfew in the affected areas, but its response since the violence first broke out is being widely criticised as inadequate.
Report: Burma violence: 20,000 displaced in Rakhine state [BBC NEWS ASIA, 28 Oct 2012] http://www.bbc.co.uk/news/world-asia-20114326
Report: Burma violence: UK to provide £2m humanitarian relief [BBC NEWS UK, 31 Oct 2012] http://www.bbc.co.uk/news/uk-20157180