Uncle Chung and Uncle Wang sent some people there to investigate things, and none of them ever came back.
8 seconds sound clip from the Kung Fu from Beyond the Grave movie soundboard.
You can hear this line at 00:03:46 in the DVD version of the movie.
Quote context
[...]
- I must leave. You better remember to take revenge for me!
- What is it? What's happened? Tell me what's happened.
- I just talked to Dad's ghost. He was murdered. I must go to Yellow Dragon Town for revenge.
- My son, Yellow Dragon is haunted.
- I can't stop you going. But please, be very careful.
- Brother, you keep that magic book. I don't want it now. I was just kidding you, you know.
- As we're from the same school, I forgive you. You can go now.
[...]