>>anewdi+Xz
An arrest doesn't need to be violent for it to be a bad act. At that point they were surrounded and would have had to push through the police to "disperse." They repeatedly asked police officers where they should go and were met with silence, so it's not clear where they were supposed to disperse to. They were arrested without the police saying a word as to why they were arresting them.
That screams of "I'm trying to figure out a way to arrest you, but I can't think of a reason. I'm going to do it anyway." Police should not be arresting journalists (or citizens!) for no reason. Being released quickly doesn't suddenly make the original act okay. It just makes it so it doesn't get worse.