Citing anonymous sources is not established ETHICAL practice, it's corruption of the system. The roll of the journalist is to get sources on the record, not let them evade accountability by hiding behind anonymity. Anonymity is something that should be RARELY granted, not routinely granted as some sort of "long established practice".
What is the justification for anonymity here? The anonymous source is oath bound not to reveal secrets, so what is so important here that justifies them violating their oath to comment on an ongoing investigation? That's what we are talking about, if they are not allowed to comment on an ongoing investigation, then it's a gross violation of their duty to do so. The journalist needs to question their motives for doing so.
We all know the answer here, that they actually aren't violating their duty. They aren't revealing some big secret like Watergate. They are instead doing an "official leak", avoiding accountability by hiding behind anonymity. Moreover, what the anonymous source reveals isn't any real facts here, but just more spin.
We can easily identify the fact that it's propaganda here by such comments about the SIM farms being within 35 miles of the UN. It's 35 miles to all of Manhattan. It's an absurd statement on its face.