The security forces are looking into the cause of the Monday’s incident, when a United Nations helicopter with at least 10 people aboard crashed in the mountains in eastern Nepal, leaving no survivors, the officials said.

It is believed that the bad weather is the cause of the accident. Krishna Bhakta Manandhar, a senior meteorologist from Nepal’ Meteorological Forecasting Division, told AFP that: “The weather where the helicopter crashed was very bad for aircraft, especially low-flying craft.”

The United Nations reported that among the ten passengers there were seven United Nations weapons inspectors and three members of the helicopter crew, but Nepal’s home ministry and local police said they recovered 12 bodies.

“We have recovered 12 sets of remains but we cannot identify any of them,” police officer Khinu Prasad Acharya told AFP.

The U.N. helicopter was returning to Kathmandu from a camp for former Maoist rebels in east Nepal. The helicopter lost contact at about 4 p.m. local time, Monday. Eyewitnesses said that they saw the chopper catch fire. It soon crashed in a mountainous region near Bhawasa, about 90 miles east of Kathmandu.

The rescue operations are being hampered by the unfavorable weather in the area.

A top South Korean officer, Lieutenant –Colonel Park Hyung-Jin might be among the victims, military officials said in Seoul Tuesday, but his death has not been confirmed yet.  

The Maoist camp in Sindhuli is one of the seven across Nepal. The United Nations has been monitoring the arms and armies of the former Maoist rebels, who signed a peace agreement with the government in November 2006.  

The United Nations have not released the identities of those killed in the tragic crash, but a U.N. spokesman, Kieran Dwyer said that they were from several countries. Today, the U.N. officials are expected to make public the names of the victims after their families have been contacted.

There are 186 arms monitors from 41 countries involved in the U.N. Mission in Nepal, CNN informs.

The United Nations will also monitor Nepal’s elections due on April 10, for a National Assembly that will elaborate a new constitution and will decide the fate of nearly 20,000 rebel fighters supervised by the U.N. in camps as part of the November 2006 peace accord.