It wasn’t a good day for gamblers in Myanmar last Saturday. A group of insurgents opposing Myanmar’s central government control of the area attacked a casino close to the Chinese province of Yunnan. In the attacks, which spilled over to security force posts, 19 people were killed, including four soldiers of the security forces, Reuters reported.

The attack occurred in Muse in the northern state of Shan. Reports indicated that as many as 100 insurgents took part in the assault, which was eventually countered by armed police and a group of paramilitaries backed by the government. The Ta’ang National Liberation Army (TNLA) claimed responsibility for the bloodbath. The TNLA is composed of fighters from the Palaung and Ta’ang ethnic groups and launch terrorist attacks in their struggle for greater autonomy for ethnic minority groups in the region.

Colonel Tar Aik Kyaw, a TNLA spokesman, was quoted by the news outlet saying the attack only targeted soldiers and militiamen who run the casino. “The militia are protecting the casinos—those casinos are the gateway for distributing drugs. Many civilians they go to the casinos and it causes many social problems, so we launched a major assault,” he said, according to the report.

The casino was never identified by media sources. Nor did they indicate the extent of the damage or how casino operations were impacted. Casinos are not legal in Myanmar, but this hasn’t stopped several from popping up along the border regions shared with China. All of the casinos are said to be run by militia and other groups.