I listened to radio traffic for the last 30 minutes before he surrendered. You would be surprised how many of the SWAT ops I've been on where cell phones were used for much of the comm traffic. Couple of reasons. Don't need to worry about scanners and cell reception is better than radio reception sometimes. It's also easier to have a conversation about tactics/orders, etc. over the phone.
2 summers ago we had a barricaded subject shooting up the neighborhood from inside his house That village was the Bermuda Triangle for our radios. Without our cell phones, we'd have been fubar.