This is ultimately the question though. The Press is the so-called 4th estate of government. They provide information to the people about how the government (and it’s agents) operate. The police didn’t tell the press to disperse, they told the protest to do so.

So are the Press part of the protest? Are they impartial and there in an objective observer capacity only (can they be?)

I don’t know the answers to those, but it’s not hard to see police using this tactic to prevent press from observing and reporting.