Detectives working on the investigation are unsure if his visits to the chatrooms were for personal use – or for surveillance.
In calls to emergency services during his rampage in the Pulse nightclub, Omar Mateen swore his allegiance to Isis – though it’s believed that he was self-radicalised rather than groomed by Islamic State jihadis.
In the days following the attack, it has been revealed that Mateen, 29, had frequented the nightclub previously.
He also used gay dating apps.
Mateen was able to obtain the weapons he used in the deadliest mass shooting in recent US history legally as he had no criminal record – despite being known to the FBI since 2013 over suspected links to al-Qaeda.
Survivors of the attack described how Mateen separated black survivors, claiming they’d suffered enough and he wouldn’t hurt them.
And an ex-Marine told how he managed to find an escape route and direct around 70 people to safety.