correspondent kyung lah. we re learning new details about the investigation. reporter: yeah. we re talking to a law enforcement official who says in order to understand a motive. they re scrubbing through his online activity, talking to family, talking to neighbors. also the same official says he was not the subject of any previous fbi investigation, meaning that there was nothing in the federal system that would have prevented him from purchasing a firearm. investigators continue to collect evidence at king soopers grocery store and search for a possible motive. a law enforcement official tells cnn among the biggest questions, the gunman s connection to this specific location. why did he drive to this boulder store 30 minutes from his home? the suspect s family home is in the suburbs of denver. the only incident on his record, an assault in 2017. he admitted he cold cocked a classmate at school. i saw a man with a beard that had possibly tactical clothing and ar-15-style