Authorities are still investigating what motivated Omar Mateen to kill 49 people at the popular gay nightclub Pulse in the early hours of last Sunday, perpetrating the deadliest mass shooting in modern U.S. history. Mateen was later killed in a shoot-out with police.
The shooting has sparked a new push for gun control legislation and Congress is expected to vote on proposals starting next week, including one on stopping people on terrorism watch lists from buying guns.
Democrats, including President Barack Obama, are framing gun restrictions as a national security issue after Mateen professed loyalty to Islamist militants. But authorities believe he was “self-radicalized” and acted without any direction from outside networks.