they have now identified the driver seen in that truck. he's a wanted man tonight. and abc's marcus moore with late reporting here. >> reporter: tonight, texas authorities naming adam curtis williams as the man seen in this surveillance image, police say crossing the border in a truck belonging to a retired couple found murdered in padre island, texas. authorities highlighting williams' distinct tattoos and gauges. the woman pictured with him now identified as amanda noverr. police still calling her a person of interest. you now have a name for the people you're looking for. how significant is that? >> that's a big break in the case. >> reporter: and investigators believe the pair crossed into mexico near eagle pass and may still be south of the border. james and michelle butler's bodies were found in a shallow grave days after family reported them missing. the retired couple was on a cross-country road trip when they vanished. last seen alive on october 15th. authorities won't say how they were killed, but that the murder was brutal. >> every homicide is brutal, and this one is particularly nasty. >> reporter: tonight, a shocked