It turns out that there are enhanced mobile phone monitoring systems in the Capitol. The government knows where you were, when you were there, and who you were. So, if you haven’t posted pictures of yourself on social media committing seditious acts or beating up policemen, or ransacking government property, or stealing documents, if nobody has identified you yet – rest assured. Once the FBI finds the time to scour all the mobile phone records, they will know exactly who you are, and then there’ll be a knock on your door.

Here is a link with more information:

How they can track every single cell phone that was carried in the Capitol invasion : CapitolConsequences (reddit.com)