A father who abducted his newborn son and is suspected of killing three relatives in Florida — including the child’s mom — was found dead from an apparent self-inflicted gunshot wound, authorities said.

The body of a man believed to be Ernesto Caballeiro, 49, was found Wednesday in rural Blanton near a white Ford van that had been sought by authorities in connection with the disappearance of 1-week-old Andrew Caballeiro, Pasco County Sheriff Chris Nocco told reporters during a press conference.

Caballeiro had apparently shot himself with a rifle. There was no sign of the man’s missing son aside from a pacifier found inside the van, Nocco said.

“All we care about right now is that we get that baby back,” the sheriff told reporters. “Our best hope right now, and what we’re praying for, is that he handed the baby off to somebody.”

The search for Andrew remained ongoing early Thursday, a Miami-Dade police spokesman told The Post.

“Our detectives continue to work tirelessly on this tragic case as we desperately seek any information on the whereabouts of this innocent baby,” Miami-Dade Police Department Director Alfredo Ramirez III said in a statement.

Cops responded to a home in rural Miami-Dade County on Tuesday and found three women dead, police said. An Amber Alert was issued early Wednesday for the missing boy.

The three female victims were identified later Wednesday as Andrew’s mother, Arlety Garcia Valdes, 40; grandmother Isabela Valdes, 60; and great-grandmother Lina Gonzalez, 84.

Ernesto Caballeiro was not immediately identified as a suspect in the women’s slayings, but investigators now believe he was responsible for the triple homicide, Miami-Dade police spokesman Lee Cowart told The Post.

While there were no signs of the missing boy in Caballeiro’s van, one witness reported seeing an unidentified blond woman in the vehicle with him.

“And I sit here and pray to God that is true, and she has the baby,” Nocco told reporters.