Police named Clem Beauchamp, 34, a suspect in the deaths Thursday, but Delray Beach Sgt. Nicole Guerriero said he has not been arrested or charged in the case.
Investigators have tentatively identified the children as siblings but have not released their names or if Beauchamp is related to them.
Beauchamp was arrested several times over the last 15 years, court records show. The most serious was in 1995, for aggravated assault with a firearm, and resulted in an 18-month sentence.
It was not immediately known if he has a lawyer.
Investigators said the girl, whose body was found Wednesday in a duffel bag, was between 6 and 10 years old. The boy, whose body was discovered later in a suitcase about a half-mile away, was between 10 and 12.
Authorities did not know how long the bodies had been in the water. Autopsy reports were not immediately released.
“We believe that this situation is domestic-related,” said Guerriero, who declined to elaborate.
Throughout the day Thursday, small boats of divers and other police combed the canal for clues. Guerriero said they found nothing.
Under a tree near the canal’s banks, a tiny makeshift memorial took shape, with a teddy bear, a hippo spotted with pink hearts and two bunches of carnations.
Neighbors said Beauchamp lives with his children from a current and past relationship in the small peach home that was surrounded by traffic barricades and yellow police tape Thursday night.
Margaret Gissone, 22, who said she is the sister of Beauchamp’s ex-girlfriend, said it’s been terrible waiting for police to identify the children, and wondering whether they are her niece and nephew.
The wide canal where the bodies were found flows east to west through this oceanside town southeast of West Palm Beach. The water is bordered by modest homes, tiny wooden docks and small motor boats, and dotted on either side with the lush green of palms and other trees.
Debbie Duarte, who lives along the canal, said the neighborhood is usually quiet. Before now, she said, the most surprising thing to turn up in the waterway was a bag of marijuana.