“We know that during the attack the gunman posted messages on Facebook saying he was doing this on behalf of ISIS. But officials have yet to find any of the precursors usually associated with radicalization. They’ve interviewed dozens of people who either knew him or had contact with Mateen.

“And they say that they’ve yet to find any indication that he became noticeably more religious, which is one of the indicators of radicalization. He still was going to the same mosque. The way he dressed didn’t change. His relationship with his family didn’t change in any way. And these are all typically warning signs that parents and friends and educators are told to look for if they’re worried that someone they’re close to is radicalizing.”