Who are these unmarked, unidentified and armed militia roaming Washington DC? Link.
Many of them are members of the Federal Bureau of Prisons Special Operations Response Teams (“SORT”). You can see some of the logos in your pictures. Here’s a closeup, for example, of one of the logos. Some also have BOP badges.
I don’t know why many of them are wearing what look like Texas flags, but I’ve seen it suggested that that’s probably the FCC Beaumont team (and you can see some FCC Beaumont insignia in some of the pictures).
One of the pictures (not from your link) looked like the guy was wearing a USMS t-shirt under his vest. I know that the USMS has a free-standing (multi-district) special response team.
I personally know a handful of federal agents who are not part of existing special response-type teams that have been deployed around the country, so I wouldn’t be surprised if these collections of folks represent a number of different federal agencies. But the short answer is that they are federal agents.
Edit:
Yes, agreed. The obviously military looking people are National Guard. I was referring to the other folks.