Law enforcement sources tell AlertsUSA post-blast investigation of all three Austin bomb scenes has revealed the explosive devices were of a sophisticated design and point to a bomb maker with a high degree of tradecraft knowledge. Components include arming switches, motion sensors and shrapnel. We have not received a definitive statement on the actual explosive materials used.

Below are three resources for general risk awareness and mitigation.

1. WiFi-enabled video doorbell w/motion sensor. Even if the current threat is of limited duration, the ability to know who enters your driveway,  approaches your door or leaves a package can be tremendously useful.

2. National Explosives Task Force Awareness Bulletin (PDF)

3. Suspicious Mail / Package Awareness Poster (PDF)