ORLANDO, Fla. – The FBI is asking for the public's help in learning more about the life of the Orlando nightclub shooter.
"We need your help through in developing the most complete picture in what the shooter did and why he did it," FBI Special Agent in Charge Ronald Hopper said during a news conference Wednesday.
Hopper said the FBI still gathering evidence at Pulse Orlando and analyzing cellphone location data to piece together gunman Omar Mateen's activities leading to the massacre, while also interviewing people who had any dealings with him.
Authorities said Mateen, a 29-year-old American-born Muslim, opened fire at the popular gay nightclub, killing 49 people and injuring 53 others.
Mayor Buddy Dyer told Local 10 News that Mateen went several places in Orlando before going to the nightclub.
"He didn't drive directly from his home to Pulse," Dyer said.
Dyer said $3.6 million has been donated to a fund created by the city for the victims and their families.
Members of the SWAT team underwent a stress-management debriefing Wednesday, as hundreds of others involved in the response to the shooting have done, Police Chief John Mina said. Further counseling is being made available.
"These are some of the bravest toughest men I know," Mina said. "No one can prepare you for what those officers encountered that night. They stood toe-to-toe and went face-to-face with a mass murderer, and I'm extremely proud of that."
A key topic for investigators is how much Mateen's Palestinian-American wife may have known about the plot.
An official who was briefed on the case but insisted on anonymity to discuss a continuing investigation said authorities believe Noor Mateen knew ahead of time about the attack. Investigators have spoken extensively with her and are working to establish whether she recently accompanied Mateen to the club, a second official who was not authorized to discuss the case publicly said.
U.S. Attorney Lee Bentley repeatedly refused to say whether charges might be brought against the wife or anyone else. He said authorities are talking to hundreds of people and investigating everyone associated with Mateen, including family, friends and business associates.
"We're going to go until we're absolutely satisfied that we've uncovered every bit of evidence that's out there and that we've reviewed every possible charge," Bentley said. "That's when this investigation will end."
State Rep. John Cortes, R-Kissimmee, is lobbying for stiffer gun laws prohibiting anyone on the FBI's watch list or no-fly zone from buying guns.
"Why are people buying assault weapons?" he said.