Uber is laying down the law in China. The ride-hailing service has ordered its drivers in China not to participate in taxi protests in the city of Hangzhou, located in Eastern China.

According to The Wall Street Journal, Uber has threatened to cancel its contracts with those who disobey its commands. The company reportedly said in messages to its drivers that it will use GPS coordinates to determine if drivers are attending the protests, which have been sparked by the rise of illegal competition for taxi drivers. Uber's harsh stance, the company says, is designed to "maintain social order."

The news comes as Uber works to capitalize on the massive Chinese market. The Financial Times reports that Uber is serving one million rides per day in China, a number that someday might eclipse the total number of rides it facilitates across the rest of the world. However, it has faced strong competition from Didi Kuaidi, formed from a partnership between Chinese internet companies Alibaba and Tencent. Uber has already invested over $1 billion into the market, and may soon raise $1.5 billion more just for China, according to the Financial Times. The company is active in 11 cities in China, and has plans to expand to over 50.