NTSB air safety investigator Dan Boggs earlier addressed media at the Mar Mak Colony Club mobile home park in Lake Worth, where he said investigators would remain for at least two days.
"At approximately 5:33 p.m. (Tuesday) a Cherokee 180 crashed here at the mobile home park," Boggs said.
The victim on the ground was in the mobile home hit by the plane, Boggs said. Authorities believe the pilot was the only person on board the plane, and Boggs was not aware of anyone else being injured on the ground -- although a neighboring mobile home was set on fire.
"We're very fortunate that in a mobile home park it wasn't larger -- and only two homes were affected," Boggs said. "The plane is destroyed."
Boggs said the Palm Beach medical examiner would be responsible for identifying both victims.
He said the aircraft had been flying from Orlando to Lantana, Florida, but that it would be a couple of days before its exact course could be confirmed. There had been no distress calls as far as he was aware but that was being investigated.
"We're wanting to know not just why the accident happened, but we also want to understand what happened and we're going to prevent it in the future," Boggs said. "Specifically, we are there to find out if anything was wrong with the airplane."
Father: 'I don't feel anything'
First responders and the sheriff's department worked through the night to secure the scene, he said.
One resident told CNN affiliate WPTV
that the plane crashed into his 21-year-old daughter's room. He said there was no response when he called out and that she did not come out of the mobile home.
"I don't feel anything -- I feel like I'm standing on air," he said. He said he'd had to call his daughter's mother to tell her the tragic news.
A Palm Beach County Fire Rescue worker told WPTV that reports had started coming in of a low-flying plane in the area moments before it crashed into the mobile home park.
Ben Goldberg was at a car dealership about a block from the crash scene and witnessed the plane going down.
"It was pretty scary, pretty surreal," Goldberg told WPTV. "I thought it was doing some sort of stunt or something along those natures. It seemed like an airshow at that close and that low a level.
"Next thing I know the thing just made contact with the ground and a big old fireball came out."
Goldberg said surveillance video recorded at the car dealership did not capture the reality of what he saw.
"The engine was loud, it was really close -- it kept coming straight through. It plays a lot slower in your mind than the couple of frames that come through on the video camera."