UPDATE: Islamic State has now claimed responsibility for the deadly massacre at the Pulse nightclub in Orlando, Florida, Reuters reported.
The man responsible for killing 50 people and injuring dozens more inside the Pulse nightclub early Sunday morning had ties to terrorism, according to multiple reports.
Omar Mateen, of Fort Pierce in St. Lucie County, slaughtered the innocent at the Pulse night club in Orlando.
A woman who lives next door to the gunman told WFTV's Jamie Holmes that their nearby apartment was evacuated Sunday morning while the FBI entered Mateen's home.
During a news conference Sunday, Sen. Bill Nelson said Mateen might have had "ties to terrorism."
Authorities are asking anyone who knew Mateen to please come forward.
Mateen was reportedly known to law enforcement, but was not the target of an investigation.
Multiple news outlets are also reporting that Mateen called 911 moments before opening fire.
Rep. Adam Schiff, a ranking member of the House intelligence committee, told CNN that Mateen pledged allegiance to ISIS before the shootings happened.
[h/t Rare]