Palm Beach Sheriff(PALM BEACH, Fla.) — Authorities are zeroing in on the age of the newborn girl who was found dead in the ocean off the Florida coast as they continued to try to determine her identity.An off-duty firefighter was boating on June 1 when he spotted the little body floating on the ocean side of the Boynton Beach Inlet, Palm Beach County Sheriff’s Office said. The newborn — dubbed “Baby June” by the sheriff’s office — was most likely 4 to 7 days old, meaning she may have been born approximately between May 25 and 28, the sheriff’s office said Thursday.Police released an artist rendering image of how the baby may have looked at birth. The baby was most likely mixed race, black or Hispanic, the sheriff’s office said.It appears she was floating in the water for about 6 to 18 hours, the sheriff’s office said. Investigators believe the baby came from Broward County, the sheriff’s office said, though authorities declined to elaborate on how authorities narrowed the likelihood down to that area.Authorities “desperately want to get to the bottom of what happened,” Palm Beach County Sheriff’s Office Special Victims Unit Captain Steven Strivelli told reporters Monday.Anyone with information is urged to call the Palm Beach County Sheriff’s Office at 561-688-4155.Copyright © 2018, ABC Radio. All rights reserved.