suddenly, he was gone. >> so investigators will be spending all weekend poring over all of the evidence that was recovered from inside the town home and also had several crime scenes. it is going to be very important here. investigators can confirm this potential isis link. if you are looking at this attack being, perhaps, the bloodiest one on american soil with ties to foreign terrorists since 9/11. you hear from the family of farouk themselves. their attorneys saying they don't want anybody to jump to any conclusions but quick to judge that they want the fbi to come up with conclusive evidence that he was radicalized. let's talk more about this with cnn law enforcement analyst, jonathan gilliam and national security analyst, peter ber kin. he is also the author of united states of jihad investigating america's home grown terrorists. let me begin with you. this radio station that is claiming the shooters were isis