MIAMI » South Miami’s Derek Medina admitted to detectives that he shot his wife “six to eight times” and indeed was the one who posted a confession and a photo of her dead body on Facebook, according to a newly released police search warrant.

The warrant, filed in Miami-Dade Circuit Court, reveals new details about the confession of Medina, whose post on the social media website has drawn worldwide attention to the killing of Jennifer Alfonso, 26.

The document also outlines the evidence seized by Miami-Dade police from the couple’s townhome, including two Samsung cellphones, three Dell computers and an iPad.

The warrant, signed by a Miami-Dade judge, asks for permission to look for evidence including electronics, and suggests that the Facebook confession and photo will indeed be key evidence for prosecutors as they prepare for a likely grand-jury indictment.

Medina, 31, is charged with first-degree murder. His arraignment is set for Aug. 29.

On Aug. 8, Medina posted a photo of Alfonso’s bloody body, bent backwards, lying on the tile kitchen floor. Her 10-year-old daughter from a previous relationship was upstairs at the time and was not physically harmed.

Medina admitted posting the admission and photo on his page — which was public — before ever calling police, the warrant said. He later walked into the South Miami police station and surrendered.

“I’m going to prison or death sentence for killing my wife. Love you guys. Miss you guys. Take care. Facebook people you’ll see me in the news,” he wrote, claiming he was tired of Alfonso’s physical abuse.

Medina and Alfonso’s Facebook pages have since been removed at the request of police.

But a self-defense claim, legal experts say, will be tough.

In his confession, Medina admits that during their argument he grabbed his Bersa Thunder .380-caliber pistol from his upstairs bedroom and pointed it at Alfonso. When she threatened to leave him, he followed her downstairs.

She grabbed a knife, but he disarmed her and put the utensil back in the kitchen drawer, according to the warrant penned by Miami-Dade Detective Terry Goldston.

“Mr. Medina then shot the victim six or eight times because she began to punch him,” the warrant said.

Miami defense lawyer Andrew Rier, who is not involved in the case, said that even if Alfonso was indeed punching or kicking him, it will be tough to prove to a jury that the physically bigger man feared for his life or imminent “great bodily harm” after disarming her.

“He was armed. She wasn’t armed, so why did he have to kill her?” Rier said.

The sheer number of bullets fired — publicly unknown until the release of the search warrant — also hampers a self-defense claim, former Miami-Dade prosecutor Matthew Baldwin said.

“For a self-defense claim to be viable and sustainable, the defendant must establish that his actions were proportionate and reasonable under the circumstances,” Baldwin said. “The fact that he shot her so many times in response to her allegedly punching him is a clear indication that he was not acting in self-defense.”

Any self-defense claim also is hurt by a Youtube video he posted days before the shooting in which he is kicking a boxing punching bag — showing he was capable of using less-than-lethal force to protect himself, experts say.

His lawyers on Friday nevertheless appeared in court asking a judge to ensure that detectives preserved all photos taken of Medina, presumably ones that might show any bruises or cuts inflicted during the episode. His lawyers were also allowed to take their own photos of him.

Medina also told police that the episode was captured on an interior surveillance video system. Police seized the video, although it is unclear how much of the confrontation was actually captured.

From the warrant, it is clear that Miami-Dade detectives were intent on investigating the self-defense claim.

They swabbed Alfonso’s hands for gunshot residue, noted blood on her hands and swabbed her knuckles for DNA. Results of any tests won’t be known for some time.

Detectives also seized a Taser stun gun, two other pistols, ammunition, a holster, as well as a large Chicago Cutlery knife from the top kitchen drawer. Crime-scene technicians also noted eight bullet casings on the kitchen floor near where Alfonso’s body was found.

Investigators also took from the townhome copies of Medina’s self-published books, a journal and other documents.