Rebels dressed as police officers attacked a number of military and police outposts in Myanmar’s restive Kokang region on Monday, killing as many as 30. The rebels reportedly belong to the Myanmar Nationalities Democratic Alliance Armies (MNDAA), a collection of armed groups waging a sustained military campaign against the government. The MNDAA claimed responsibility for the attacks on Facebook, saying they were conducted in self-defense.

Myanmar’s State Counsellor Aung San Suu Kyi’s office released a statement saying, “According to initial information, many innocent civilians, including a primary school teacher, were killed because of attacks by the MNDAA armed group.”

Myanmar is host to a number of competing insurgencies and separatist factions who have waged campaigns for decades following Myanmar’s independence from the United Kingdom in 1948. There are over 20 armed groups operating within the country, some of them with significant numbers and autonomous control over certain regions.

Counsellor Kyi has long been a prominent international political figure, having endured 15 years of house arrest as a result of her political activities against Myanmar’s previous military regime. She was awarded the Nobel Peace Prize in 1991 for her symbolic resistance and for being “an example of the power of the powerless.” She has championed Myanmar’s arduous transition to a more open and democratic system, but it has been fraught with resistance and conflict.

In addition to navigating the political complexities of uniting the hundreds of ethnic groups that live within Myanmar, the state counsellor must contend with repeated violent attacks by the various armed groups in the country’s more rural areas.

Kokang, the site of the most recent attack, straddles the border with China and has a heavy Chinese influence. Locals speak Chinese and use Chinese money as their currency. Fighting in the region has raised tension between the two countries, as China fears instability and a possible refugee crisis along its border.

In addition to attacks by separatist movements, accusations of ethnic cleansing have been leveled by U.N. officials and Amnesty International against the Myanmar government. A Muslim minority in a separate region of Myanmar has been caught in “anti-terrorist” raids by the government following a major military operation launched in October. Satellite images have shown villages burned to the ground, but responsibility cannot be ascertained as foreigners are not permitted in the area.

It has been reported that as many as 30,000 Muslim refugees have been displaced by the fighting, fleeing into neighboring Bangladesh.