Confirming or otherwise whether he has been arrested is NOT going to prejudice any (possible?) forthcoming action, so why the secrecy?
Let me put it another way; do you actually KNOW what is happening? Are "various agencies" actually keeping you in the loop, or are you just hoping that it is about time that his (alleged) nefarious behavior is being dealt with by an agency with the ability to track and bring to justice someone who has (again, allegedly) committed crimes in a variety of international jurisdictions?
My best guess (and call it an assumption if you prefer) is that you haven't got a clue what is happening right at this time, but rather you are hoping that any scraps of information that you might provide to "various agencies" might help further the cause.
I applaud the cause, but don't much care for subterfuge when it comes to passing on up to date information. There was a time when it was newsworthy and interesting to read.
Might I suggest that you report nothing when you have nothing, and refrain from the " I just heard something, but sorry I am not able to tell you," tease.