The Louisiana gunman who murdered eight children — including seven of his own — before he was killed was a 31-year-old Army vet who posted a picture of himself with one of his daughters hours before Sunday’s massacre.

Shamar Elkins unleashed his unthinkable carnage at three addresses in Shreveport shortly after 6 a.m. Central Time, authorities said.

The slain victims ranged from 1 to 14, and there was audible gasping as a police rep read out their ages at a press conference Sunday.

Elkins also shot two women in the head, with one described as in life-threatening condition.

Elkins was subsequently chased by local police, who shot him dead as he drove into neighboring Bossier City.

On his Facebook page, Elkins shared a picture of him with his eldest daughter as she ate a burger Saturday, hours before his rampage.

“Lol!!!! Took my oldest on a lil 1 on 1 date had to catch her down bad ugh ugh,” the killer wrote, along with a string of laughing emojis.

Two weeks ago, Elkins shared a picture of himself posing with seven children, calling them “all my kids,” as he described taking them to church for an Easter service.

“Happy Easter had a wonderful time at church for the first time with all my kids what a blessed day,” he wrote in the Facebook post.

But Elkins also hinted at mental-health struggles in another recent Facebook post, where he called for God to “guard” his mind.

“Dear God, Today I ask You to help me guard my mind and my emotions,” read the post dated April 9.

“When negativity arises, remind me to say, ‘It does not belong to me, in the name of Jesus,’ ” he said.

“When depression tries to settle in, when anger rises, when anxiety or panic comes, give me the awareness to recognize what is not from You and the strength to reject it immediately in the name of JESUS.”

The mass murderer’s wife previously shared a picture of Elkins in a US Army uniform in 2016, as she awaited his return from active service.

“Been waiting for yu [sic] 5 more days… And yu all mines. Damn bby I gt to fatten yu up,” she wrote at the time.

In March 2019, three years after completing his service, Elkins was arrested on a charge of illegal use of weapons and carrying a firearm on school property, KTBS reported.

He was just 300 feet away from a Shreveport high school when he fired five rounds at a car — precisely in the direction of the school — as it sped away, according to a police report obtained by the outlet.

He pleaded guilty to the illegal weapons charge in October 2019 and was placed on probation for 18 months. The firearm charge was dismissed.

Sunday’s shooting is now being handled by Louisiana State Police as it crosses parish boundaries.

Louisiana Gov. Jeff Landry said he and first lady Sharon were heartbroken over the events.

“We’re praying for everyone affected. We’re deeply grateful to the law enforcement officers and first responders working tirelessly on the scene,” Landry wrote on Facebook.

US House Speaker Mike Johnson, who was born in Shreveport, wrote on X, “Heartbreaking tragedy in Shreveport this morning — 8 children were senselessly killed and multiple others were injured.

“My team is in touch with local law enforcement as more details emerge,” he said.

“We’re holding the victims, their families and loved ones, and our Shreveport community close in our thoughts and prayers during this incredibly difficult time. And we are grateful to the Shreveport, Bossier, and Louisiana State Police for their swift response,” Johnson added.