Oh my goodness I am glad the girls got inside safely. Yay girls!
City dwellers birds of prey include hawks, falcons, merlins and owls so....beware for sure.
I was sitting in the drive-thru at the electric company one day and this pigeon came racing by my van and right behind her a redtail hawk. She never stood a chance. Bless her heart the hawk snatched her right out of the air.
The most important thing to remember about hawks and why they are so lethal for chickens is an old story my grandfather told me as a child that I have come to watch and see the truth of.
The eagle will soar a mile high and see a mouse in a field and dive....he sees the field, the mouse, the house, the pond and the man on the tractor. They see the full picture.
The hawk in that same scenario only sees the mouse and they rarely miss. That is why they dive into fences and such...they never see them until the last possible second. They see only their target.
So, if it was perching there, it will be back because it missed its chance. As it is a juvenile, it may actually get lost and get sidetracked but watch for him to come back and keep your girls safe.