YANGON - The United Nations on Monday voiced alarm at an upsurge of fighting in Myanmar's northern state of Kachin, as shelling was reported near civilian areas and rebels said clashes could spread.
There has been heavy fighting in Kachin, near the border with China, since the army's surprise artillery attack on a Kachin Independence Army (KIA) training camp last week, which cast doubt over faltering peace talks.
The United Nations called for civilians to be protected in the fighting, which has caused around 100,000 people to flee their homes since a 17-year ceasefire ended in 2011.
"We are concerned by reports of renewed hostilities in Kachin State, particularly reports of shelling in the vicinity of villages and camps for internally displaced people," said Pierre Peron, spokesperson for the UN Office for the Coordination of Humanitarian Affairs.
The powerful army has admitted carrying out Wednesday's attack on the KIA training camp, which the rebels say killed 22 recruits from various ethnic groups near its border stronghold of Laiza.
But the military said it was a warning shot in response to KIA attacks.
Local aid groups and the KIA have said shelling has continued, with heavy weapons fire near camps housing thousands of displaced people on Sunday. The camps themselves were not hit.
Rebel spokesman La Nan said the military could erode the trust of all ethnic groups by blaming the KIA for provoking its artillery attack.
"It could create fighting all over the country," he told AFP.
There is growing concern that months of painstaking negotiations between the government and multiple ethnic minority armed groups have reached an impasse over key issues -- such as the potential for the armed groups to continue to exist in some form.
In an interview last week with the Voice of America, army chief Min Aung Hlaing said the military was entitled to defend itself, including acting preemptively "to stop them (rebels) from being able to fight".
He rejected the idea that ethnic groups could continue to bear arms, but added: "We really want peace".
Some 14 of the 16 major rebel groups have signed ceasefire agreements with the quasi-civilian government as part of reforms in recent years. But deals with the KIA and the Ta'ang National Liberation Army in the eastern state of Shan have proved elusive.
A small group of protesters carrying candles gathered in central Yangon at dusk on Monday to protest at the recent attacks.