These are very common. The NYPD and FBI have just now starting busting them up.
Many people don’t know this since they think the the USA’s late imperial citizenship model is universal, but the Chinese state claims global jurisdiction over all Chinese persons and they don’t determine who is a Chinese person on the basis of papers issued by foreign governments.
We always knew that, and they always knew that too.
Until recently, we considered this not a factor, because most Chinese students would stay in the US or come back later, so we could get a constant flow of highly trained individuals with most of their training having been financed by someone else.
Now things are changing, globalization is being reverted, and the benefit equation has changed, because now, as those students get back to China, it is now us the ones financing the fixed costs of the educational infrastructure to benefit China.