More than 30,000 people have fled Burma’s restive Kokang autonomous zone in the aftermath of an attack by the region’s dominant ethnic armed group on the administrative capital Laogai earlier this month.

Dozens of Burmese soldiers have been killed in several clashes between ethnic rebels and the army in Kokang along the border with China, state media reports.

Aid workers and those displaced have expressed fears of a more violent and protracted conflict than a previous flare-up in the Kokang region in early 2015.

China’s Foreign Ministry said on Thursday more than 20,000 people from Burma are seeking refuge in China from fighting in northern Shan State, as fighting threatens Burmese leader Aung San Suu Kyi’s top goal of reaching peace with minorities.

China on Tuesday called for an immediate ceasefire between ethnic rebels and Burmese security forces in the restive border area of Kokang, urging the two sides to resolve their differences through peaceful means instead.

The Kokang Self-Administered Zone’s capital Laogai, in northern Shan State, came under attack early Monday morning, with a spokesman for the coalition of ethnic armed groups identifying itself as the Northern Alliance saying one of its members was responsible for the assault.