The restriction came after the UN took a decision to raise the security warning to level two after a meeting on October 28 in its Dhaka office.

The decision was taken after two of its staff were attacked twice at the Kutupalong Rohingya refugee camp by a group of refugees and outsiders. UN assistance to the camp has been suspended since October 13 because of security reasons.

A World Food Programme (WFP) field official, Mehnaz Khan, was manhandled by the refugees at Kutupalong camp on September 23.

On October 12, as a UN High Commissioner for Refugees (UNHCR) car was travelling from Teknaf to Cox's Bazaar carrying non-Bangladeshi UN staff, including the head of WFP Dhaka office, Douglas Coutts, it was surrounded by hundreds of refugees opposing repatriation in front of Kutupalong camp. Police later escorted out the UN team.

"Our staff no longer feel safe. Until the safety level is restored we cannot reenter the camp and provide assistance," Jorgen Lissner, resident coordinator of the UN in Bangladesh, told The Daily Star.

Lissner said the Ministry of Food and Disaster Management has been informed about the incidents.

"We are hoping that they (the ministry) will take some steps to ensure security at the camps so that our staff can go back and assist the refugees," said Lissner.

Superintendent of Police (SP) of Cox's Bazaar Syed Towfique Uddin Ahmed told The Daily Star that criminals at Kutupalong camp are creating trouble and raids would be carried out soon to arrest them.

Since the first attack on September 23, a group of refugees enforced strikes in eight schools and closed down a sewing camp for women refugees at the camp.

About 2.5 lakh Rohingya refugees took shelter in Bangladesh in 1991 following a crackdown on them by the Myanmar military junta. Many of them repatriated after an accord signed between the two countries in 1992. But a good number of them are still staying back.