Heavy fighting continued Monday between government forces and an ethnic minority rebel group in northern Burma, with reports of casualties on both sides.

The fighting between the Kachin Independence Army and government forces broke out last week in Kachin State not far from the Chinese border. VOA's Burmese Service reports that the rebels have lost three of their camps and government forces are closing in on other rebel positions.

There are reports some residents have fled across the border. But VOA's Burmese Service reports that most of those crossing the border may be Chinese citizens who were working in Burma.

Two years ago, more than 30,000 Burmese refugees fled into China to escape fighting in Burma's Kokang region.

The Kachin Independence Army, like several other ethnic militias in Burma, signed a ceasefire agreement with the central government several years ago. But those agreements began to break down in 2009, when Burma demanded that the militia groups come under central authority and serve as part of a national border guard. That prompted some militias to resume fighting.

It is almost impossible for outsiders to confirm reports about the fighting. The border areas are largely off limits to foreigners and journalists.

Last year Burma held its first election in 20 years, in what the former ruling military council called a step toward full civilian control. However, rights activists and several governments, including the United States, say the election was flawed and solidified military rule.

A number of countries have imposed sanctions on Burma's government because of its human rights record and lack of progress in political reforms.