they have been painstakingly looking through this lake, concentrating right underneath that foot bridge. it's a bridge where there's still two divers underneath slowly going through this water. it has been a challenging day. rainy, cold, still trying to find evidence to understand this very difficult and complicated case. tonight for a second straight day, fbi dive teams are combing the bottom of the san bernardino lake searching for crews. >> we did have a lead that indicated that the subjects came into this area. we're seeking evidence of anything that had to do with this particular crime. >> reporter: the killers tried to hide and destroy evidence, including smashing two cell phones found in a garbage can near their home. other electronics are missing, including a computer hard drive. that missing hard drive could be the reason for the underwater surge. its discovery could help investigators still trying to