China’s tobacco regulator threw a monkey wrench in the businesses of several vaping startups Friday when it issued a notice asking online platforms and businesses to stop selling electronic cigarette products.

The move is aimed at stopping kids from buying e-cigarettes through the internet, Reuters reported.

The notice follows broad efforts to limit e-cigarette sales to minors in the New York and other states, and amid an international scare about the health effects of vaping.

China Tobacco, the state-run monopoly that controls the sale and distribution of all tobacco products to the nation’s 300 million smokers, published the take-down notice Thursday.

Chinese startups trying to get a portion of the enormous potential market for e-cigarettes have launched products similar to Juul, the popular US e-cigarette company that’s caught significant criticism for marketing flavored smokes to kids. Juul halted sale of its flavored products last month as the federal Food and Drug Administration completes a safety review.

RELX Technology, founded by former employees of Uber China, and SnowPlus, founded by a team of former bitcoin entrepreneurs, are among the Chinese market leaders. Both companies told Reuters they would stop selling online.

An official Juul online store briefly appeared on Chinese e-commerce sites in September, but disappeared days later.