Thanks to a WSB reader tip, which we just confirmed with an in-person check, we know that ATF, the federal agency that investigates arson among other things, is now at the 4132 Cali fire scene. (This is what the project was supposed to look like, by the way.) From our understanding, ATF presence does not necessarily mean they know it was deliberately set, but there is some reason they want these specialists to be there taking a look. Also at the scene, the following photos (taken from the north side of First Mutual Bank, as 2nd photo shows); one firefighter was atop the ladder as another one joined him/her — what a perspective on the scene they must have: