Others have noted the outline of what looks like a body-armor chest plate under the sweatshirt. Looks like a trauma plate to me too.
Weather station a few blocks away was recording 87 degrees with a 76 dewpoint (70% humidity) (i.e., stifling, tropical-like heat) when he walked into that church. Was still 85 degrees when he walked out. That’s not sweater weather by any stretch of the imagination.
Wanted poster says 5’ 9” 120 lbs. He is wearing something under that shirt, When I was that size, I was very skinny.