A 64-year-old man identified by authorities as the shooter who killed at least 50 people and injured 200 others in Las Vegas lived in Florida as recently as 2015, according to property records.
Stephen Paddock lived in Melbourne from 2013 to 2015, records show.
WKMG, the CBS affiliate in the Orlando market, is working to uncover more details about Paddock, who killed himself after the worst shooting in U.S. history. The 2016 shooting at Pulse nightclub in Orlando, where 49 were killed, previously held the infamous distinction.
Some family members of Paddock live in Orlando.
"We are completely dumbfounded," Eric Paddock, the brother of Stephen Paddock, told the Orlando Sentinel. "We can't understand what happened."
Eric Paddock also told the newspaper that he has already made a statement to police.
"We are thinking of all of those affected by the horrific mass shooting in Las Vegas," Orlando Police Chief John Mina said in a statement. "This community, and the men and women of OPD, know all too well the anguish that is gripping the residents, visitors and law enforcement community in Las Vegas. We grieve with the people of Las Vegas, and stand firmly with our brothers and sisters in law enforcement who are dealing with this tragedy. Our condolences and prayers go out to the families of all those affectd, and we grieve with LVMPD, who lost an off-duty officer who was attending the concert and was shot and killed."
My heart is breaking for Las Vegas. I know this feeling all too well. Our Pulse family is with you. ♥️— Brandon Wolf (@bjoewolf) October 2, 2017
Las Vegas Metropolitan Police Sheriff Joseph Lombardo told reporters that police responded after reports of shots being fired from the Mandalay Bay toward the Route 91 Harvest festival around 10:08 p.m. Sunday local time.
"We determined there was a shooter on the 32nd floor of the Mandalay Bay," Lombardo said.
Officers engaged the suspect, whom Lombardo described as a "local resident," and killed him.
"Right now, we believe it's a sole actor, a lone-wolf-type actor," Lombardo said.
Authorities said families looking to locate missing loved ones can call 866-535-5654.
Concertgoers describe shooting
Three people who were attending the concert at the Las Vegas Village outdoor arena when gunfire broke out described hearing the sound of gunfire while country music star Jason Aldean was performing.
Aldean, his wife Brittany, his band and crew were able to get offstage safely and unharmed.
"We were close to the stages -- about six rows from the front on the left-hand side, and he was just performing," Rachel Dekerf said.
"People went down on the Mandalay side of the stage," Joe Pitzel said. "I don't know if people were ducking or if people were hit."
Derkef filmed her escape from the venue using her cellphone, starting just after the first shots were fired.
She described ongoing gunfire and played out the video she had recorded during which more than five minutes of gunfire were intermittently audible.
"The gunshots lasted for 10-15 minutes. It didn't stop," she said. "We just ran for our lives."
'Sounded like firecrackers'
Eyewitness Bryan Heifner spoke to CNN from a room in a hotel across from the Mandalay Bay, which he said he could see from his window.
"Mostly I heard the shots, just so many shots -- I just thought it was a semi braking with the air brakes, but then I went downstairs and saw people running and looking for family," he said.
"I immediately went back to my room, locked the door, turned the lights off."
Another witness told CNN affiliate KSNV-TV that the shooting sounded like firecrackers at first.
"It didn't sound normal, it sounded like machine guns and it was like several rounds, it was like hundreds of rounds," she told the news station.
"My boyfriend had me move behind a building here because it just didn't sound right," she told KSNV. "And then we hid behind a building and we could just hear hundreds of rounds going off and then about 10 minutes later the police came and just blocked off all the streets."
She said she was about a block from the Route 91 Harvest festival.