Authorities now have video evidence of the man accused of killing his wife and then posting a picture of her bloody body on Facebook.

From a home surveillance video, Derek Medina can been seen walking away from a confrontation with his wife Jennifer Alfonso before returning moments later to fire a gun.

The weapon can't be seen in the video released Tuesday by the Miami-Dade State Attorney's Office to The Miami Herald. But the camera did pick up the swirl of gunpowder in the air from when authorities say the 31-year-old fatally shot his 26-year-old wife at their South Miami home.

The footage also shows Medina calmly retrieving a jacket and his phone, apparently stopping to take a photo of Alfonso's body and then walking out of the house.

After leaving, Medina posted the photo of his dead wife on Facebook, along with a confession. In the photo, Alfonso's lifeless body laid twisted, knees bent backward.

Pleading not guilty, Medina has claimed that his wife was the aggressor and that he was acting in self-defense.

The new evidence may put a dent in Medina’s claim that he armed himself with a gun only after Alonso began punching him, and then shot her while she wielded a knife, according to court documents.

The murder took place on August 8, after the couple got into a verbal argument which led to Medina shooting Alonso six to eight times in their kitchen while Medina's 10-year-old daughter, from another woman, was still inside the house. 

Medina is charged with second-degree murder, but The Miami Herald reports prosecutors will likely seek a first-degree murder indictment when the grand jury returns in September. A judge has set a tentative trial date of Nov.4.

Based on reporting by The Associated Press

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