Then he arrived in Hong Kong and his mobile phone had no signal, so he lost contact
Good situation
Bad situation, He might be carrying something (drugs or something), or he is a wanted person online and is in jail and no contact is allowed.
Also, do you know your friend’s situation?
Is he a good guy or a criminal?
It is also possible,
He was pulled to assist in the investigation. Maybe he knew someone involved in a criminal case
He was pulled to take a statement. Every citizen of the People's Republic of China has the obligation to assist the police in investigating cases
It is also possible,
Knowing people, knowing faces but not knowing people,
It is also possible, knowing people Knowing the face but not the heart, that person is a criminal, but you just know it
It is also possible that that person is a criminal, but you just don’t know it
It is also possible that that person is a criminal, but you just don’t know it
It is also possible that that person is a criminal, but you just don’t know it You just don’t know it
It’s possible that that person is a criminal, but you just don’t know it
It’s also possible that that person is a criminal, but you just don’t know it
It's also possible that that person is the criminal, but you just don't know it.
There is another possibility
If your friend is a drug addict or something, he accidentally brought drugs when he went abroad and was stopped
I am now sure
This is definitely not a problem with the pass. Under normal circumstances, the pass will not allow entry at most, but it is not that mysterious. In fact, when people at the border stop you because of culture or other reasons, they will say that there is something wrong with your documents, passport, pass, etc., and then pull you into a room and do what they want to do
Finally, I want to ask, is this friend so important? You are so worried about him. Also, does his family know? How did his family react?