China is no stranger to food safety scandals, but there may be something more sinister at play in the latest deadly food mishap in China’s Xinjiang region.

The Xinhua news agency reports that authorities are investigating how 11 people were killed and more than 100 made sick after ingesting anti-freeze stored in vinegar bottles. The poisoning happened during a Ramadan holiday meal in village outside of Hotan – one recent site of unrest among ethnic Uighurs. The poisoning could be just another case of deadly Chinese food, but it does arouse suspicion given ongoing tensions in the region between majority Han Chinese and Muslim Uighurs.