FBI Investigates Whether Orlando Gunman Omar Mateen Visited Pulse Before Massacre

The FBI is looking into the possibility that Omar Mateen visited Pulse nightclub and tried to communicate with some of its patrons on a gay dating app before he gunned down 49 people at the club in Orlando, authorities told NBC News on Monday.

Cord Cedeno, a customer at the club, told MSNBC-TV on Monday that Mateen tried to get in contact with him through Grindr, a dating application for gay and bisexual men, but that he blocked Mateen "because he was creepy."

Cedeno said that after Mateen killed 49 people and wounded 53 others at Pulse early Sunday, "I recognized him off Grindr." Mateen, 29, was killed in a shootout with police after a three-hour standoff.

"That's not his first time there," Cedeno said. "He's been there several times. I know that for a fact."

An FBI official told NBC News that investigators are reviewing similar reports, as well as statements by members of Orlando's gay community who said they recall having seen Mateen at the club several times before.