THE gunman who opened fire in the Pulse gay nightclub in Orlando used Facebook to search for news of the atrocity while he was carrying it out, it was disclosed yesterday (Thursday).
In an open letter, Ron Johnson, chairman of the committee on homeland security and governmental affairs, asked Facebook to release the full details of Omar Mateen's postings on the site before and during the Orlando attack, during which 49 were shot dead.
Mateen apparently searched for "Pulse Orlando" and "Shooting", while the attack was taking place, according to the letter.
A source close to the investigation said Facebook had already handed over the details from Mateen's posts about the attack, which were made just moments before he began firing, to law enforcement and were cooperating fully with the investigation.
"Now taste the Islamic State vengeance," he wrote on Facebook, denouncing "the filthy ways of the West" and adding "may Allah accept me".
He also called a local television network during the attack to make sure they were aware of his actions, and called 911 to pledge allegiance to Islamic State of Iraq and the Levant.
Mr Johnson asked Facebook to release further details on Mateen's Facebook usage by June 29.
The senator said that Mateen had used five Facebook profiles.
In what Mr Johnson described as the gunman's final post, he wrote: "In the next few days you will see attacks from the Islamic State in the USA."
President Barack Obama arrived yesterday in Orlando to visit survivors and relations of victims. Fifty-three were injured in the attack.
Yesterday it emerged that the shop where Mateen tried to buy body armour had called the police, after he demanded military-grade equipment then made a phone call, talking in what they believed to be Arabic.