Police are looking for gunman they say walked up to a mobile home in the Regency area Tuesday afternoon and opened fire, killing a woman and her roommate.
Richard Barley, 42, died at the scene and Kelli Daidone, 40, died at a hospital overnight, police said.
Police were called to the double shooting in the 10200 block of Spivey Terrace just after 4 p.m. Tuesday.
Daidone's sister, Tawni Day, said she must have known the person who fired the shots or she would not have opened the door. She believes the crime is drug related, but her sister didn't deserve to die.
Day said her sister leaves behind two children.
"She had a good sense of humor. She had a good heart," Day said.
In fact, Day said her sister took in Barley a couple weeks ago while he was trying to get his life together.
Police have not said what led to the shooting, only that they are looking for one or more gunmen.
Ed Spivey, who owns the mobile home park, said he's not sure what happened. He said the mobile home park is normally a safe place.
"People wouldn't live here if (it weren't)," Spivey said. "For 45 years it's been safe. Why would it all of a sudden (not be)? But you have to be on guard against drugs."
Anyone with information about the double killing is asked to call the Jacksonville Sheriff's Office at 904-630-0500 or Crime Stoppers at 866-845-TIPS.