It says that the perp is Pakistani, and that he's been charged, but not that he's been arrested -- so he's presumably still free in Pakistan.

I hear that normally what the FBI would try in such cases is to lure people onto US or extraditable territory. IIRC there were some rogue Chinese chemists, who owned companies that sold fentanyl intermediates and were under secret indictment in the US, who were "invited to a VIP academic conference in Hawaii" and then arrested as soon as their flight landed.

Seems clear that this Pakistani is a bit more circumspect.