YANGON (AFP) - Up to 30,000 people have been displaced by violence in Myanmar's Rakhine state, half of them over the course of last weekend when dozens of people died in clashes with the military, the UN said on Friday (Nov 18).

Troops have poured into a strip of land along the Bangladesh border, an area which is largely home to the stateless Muslim Rohingya minority, since coordinated attacks on police posts last month.

The army this week said troops have killed nearly 70 people as they hunt the attackers, although activists say the number could be much higher.

Violence escalated over the weekend, with state media reporting troops had killed more than 30 people in two days of fighting after coordinated ambushes forced the army to bring in helicopter gunships.

The UN's Office for the Coordination of Humanitarian Affairs (OCHA) said 15,000 people were believed to have fled their homes over the space of 48 hours.

"Up to 30,000 people are now estimated to be displaced and thousands more affected by the October 9 armed attacks and subsequent security operations across the north of Rakhine State," said a spokesman for the UN OCHA.

"This includes as many as 15,000 people who, according to unverified information, may have been displaced after clashes between armed actors and the military on November 12-13."

Activists have accused troops of killing civilians, raping women and torching homes - allegations the army denies.

Authorities have heavily restricted access to the area, making it difficult to independently verify government reports or accusations of army abuse.

The resurgence of violence in western Rakhine state has deepened a crisis that already posed a critical challenge to the new administration led by democracy activist Aung San Suu Kyi.

More than 100 people died in 2012 in clashes between the majority Buddhist population and the Muslim Rohingya, and tens of thousands of them were driven into displacement camps.