Exactly what I thought!
Sorry 'bout that.
Since they’ve released the photo and it matches the person in the video…. I’m pretty sure it’s this guy
The older Bob Crimo who ran for mayor and is the owner of that Facebook page is definitely either the father or closely related, his photo is in this news article:
https://www.chicagotribune.com/suburbs/highland-park/ct-hpn-city-election-preview-tl-0321-story.html
Compare to the photo of the suspect - very distinctive nose and mouth.
The Facebook page for Bob Crimo appears to have been taken down.
It’s still there for me.
What we see is apparently the father’s page.
It does look like the son (person of interest) has either taken down his page or it’s been taken down for him.
I was able to access it, although not directly.
This is the father’s business, closed several years ago but still has a Facebook page.
Talking head on CNN saying that police will try to talk to anyone who knew the suspect including “girlfriends or former girlfriends”.
Uh, guys, you probably won’t spend much time on that.
What a total loser this scumbag Crimo looks like. Oh, whoops, there I go repressing his individuality. Fuck him.
Heavy has 5 fast facts about him:
Sounds about white…
They are saying they captured him following a brief chase.
Local ABC news affiliate (WLS) is saying the same.
He’s still a “person of interest,” and not a “suspect”? 
He looks like the kind of person who would commit such a horrific act. So glad he’s in custody. They just have to match the prints in the gun to him, then we wait a few years for the trial while he lives in taxpayers’ money.
That’s the usual phrase used in such cases.
Good to know.
ETA: They’re finally explaining it on the news; it basically comes down to local laws where the person is apprehended, and what the laws say about charges being filed. (Apparently, most departments in this area still use “suspect.”)