Well it's more complex now. There is a special unit for NSL matters, and the NSL permitted the state agencies to openly operate in HK (they were thankfully already operating but not openly), but I think it's mostly done with the coordination of the NSL unit, which is also connected to police. So probably some of the people in the raid were staff from the NSL unit.
https://www.scmp.com/news/hong-kong/law-and-crime/article/30...