The gunman in Sunday's attack at an Orlando gay nightclub used Facebook "to search for and post terrorism-related content" before and even during the assault, according to Wisconsin Sen. Ron Johnson.

On the day of the attack, Omar Mateen apparently searched Facebook for "Pulse Orlando" — the name of the nightclub where 49 people were killed — and "shooting," Johnson, head of the Senate Committee on Homeland Security and Governmental Affairs, said in a letter to Facebook founder Mark Zuckerberg.

He said Mateen also apparently posted the following messages:

  • "America and Russia stop bombing the Islamic state..I pledge my allegiance to abu bakr al Baghdadi..may Allah accept me." (Baghdadi is the leader of ISIS).
  • "The real muslims will never accept the filthy ways of the west."
  • "You kill innocent women and children by doing us airstrikes..now taste the Islamic state vengeance."
  • And finally: "In the next few days you will see attacks from the Islamic state in the usa."

As The Two-Way has reported, investigators say Mateen pledged allegiance to ISIS in a 911 call during the attack — but "officials said they haven't seen a direct link between the gunman and the terrorist group."

Mateen is "apparently associated" with five Facebook accounts, Johnson says, and was also using the social media platform to search for terrorism-related content prior to the attack. The Republican senator adds:

"[M]y staff learned that in May 2016, Mateen used Facebook to search for information on the San Bernardino terrorists and on June 4, 2016, Mateen apparently searched for 'Baghdadi speech.' My staff has also learned that Mateen apparently used Facebook to conduct frequent local law enforcement and FBI searches, including searching for specific law enforcement offices."

Johnson called on Facebook to assist his committee's inquiry into the attack by providing "all Facebook data on Mr. Mateen's activities on his account and any affiliated Facebook accounts."

As NPR's Nathan Rott tells our Newscast unit, it's still unclear whether "Facebook has or will respond to the request."

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