Sorry, we murdered the wrong guy.

That’s what members of the deadly Trinitarios street gang told grieving relatives of Lesandro Guzman-Feliz, the 15-year-old Bronx teen dragged from a bodega and slaughtered like an animal on the street, the family said Saturday.

“I’m sorry,” one of the messages from a “top leader” said, according to Derek Grullon, 19, the boyfriend of the victim’s sister, Genesis.

“I know it doesn’t mean a lot. It wasn’t supposed to be him,” the message continued.

And as if it was any consolation, the gang-banger affirmed in the two-minute Snapchat recording that the savages responsible have been booted from the notorious Dominican crew.

“He [the gang leader] said they kicked all of them out of the gang,” Grullon said.

“We cried,” Grullon said of hearing the messages. “He was innocent.”

Police sources told The Post that investigators believe the Trinitarios may be involved in both Guzman-Feliz’s death and the serious injury of a 14-year-old stabbed more than a dozen times Monday afternoon at Bronx River Parkway and Gun Hill Road.

The tragic mistaken-identity slaying may have been sparked by a raunchy sex video, two high-ranking police sources said.

Detectives are probing whether Guzman-Feliz’s murderers mistook him for a similar-looking, curly-haired youth who faces the camera prominently in a homemade sex video posted on Facebook.

A nude young woman having sex in the video may be related to one of the attackers — and cops are investigating whether he rallied his friends to seek revenge, only to slaughter an innocent teen, the sources said.

The senseless, unexplained slaying of a good kid who had never been in trouble, and who in fact had dreamed of becoming a cop, has tormented his wide circle of family and friends — and no one harder than his mother.

“He was my angel,” his mom, Leandra Feliz, 48, said Saturday.

“He was a sweet child,” the mom told The Post of the teen whom all who loved him knew as “Junior.”

“But they killed my son like he was junk.”

A snazzy dresser who liked jeans and Air Jordans, “Junior” dreamed of one day being a police detective.

The teen was enrolled in the NYPD Explorers program, a group for youth ages 14 to 20 who are interested in a career in law enforcement, police sources said.

“Since he was 5 years old, he told me, ‘Mommy, I want to be a police,’ ” the mother recounted.

“He loved the police car,” she added, using her hands as a steering wheel. “[He said], ‘I wanna drive the police car,’ ” she recalled of her child as a boy.

Instead, on Wednesday night, Guzman-Feliz met his end just a block from his family’s apartment on Bathgate Avenue.

Surveillance video from the Cruz and Chiky grocery shows Guzman-Feliz being dragged out of the bodega by his hood.

His five attackers then joined in holding him down and hacking and stabbing him to death, one swinging into him with what appears to be a machete and another jabbing him repeatedly with a smaller knife.

Mortally bleeding from the neck, Guzman-Feliz ran toward nearby St. Barnabas Hospital but collapsed just feet away, police said.

Rushing to see him, his mother screamed at hospital staff, she recalled: “He is alive? He is alive?”

The mom knew the hospital well — she works in the intensive care unit as a housekeeper.

But her son never made it to the unit. By the time she saw him, he was already dead.

“They stabbed my son in the neck, in the main artery going to the heart,” the mom said doctors told her.

Speaking in her neat, cozy living room Saturday, the Dominican Republic native received a stream of mourners of all ages.

She grasped her neck as if reliving his pain.

“The opened a hole in his neck with a machete,” she said through tears.

“That’s why my son die,” she said. “I hugged and kissed my son,” the mother recalled of her grief at the hospital bed of her fourth and youngest child.

“I said, ‘Oh my God! Who am I going to wake up to go to school?’ ”

The brutality shocked even hardened NYPD brass.

“The stabbing murder of this young man is among the most brutal crimes I’ve seen in my 36-year career,” tweeted Chief of Department Terence Monahan.

The news of just how senseless and avoidable her son’s death — captured on the now-viral video — is only added torment for his loved ones.

“Tell me, what bad thing that a kid like that do? Five men with machetes?” the mom railed. “A kid with no weapon. Alone. Why kill him like that?”

She added, “He was just waiting to graduate and study criminal justice. And be a police.”

“I have no reason to live my life,” she added through tears. “They kill him. They kill me, too. I’m ready to die. You can put me with my son.”

The thugs remained at large Saturday.

Detectives are “still sorting out tons of information/misinformation,” another police source said.

Meanwhile, neighbors joined the mom in railing against the bodega owner for not interceding.

“He knows him since he was a baby,” the mom said. “You know what kind of child he was. He wasn’t a bad kid. He could call the police right away and try to help him.”

Bodega staff declined to speak to The Post on Saturday.

“I will never see him graduate from high school. He was going to be in 11th grade,” the mom said.

“It pains my heart. I’m not going to see him go to his prom. My daughter had a prom, and I was telling him I’m just waiting for your prom now.

“I’m not going to see him get married, have kids. I’m going to have nothing from him.

“That’s not going to happen, not going to happen. And nothing is going to bring my child back.

“Not even them arresting all those killers is enough. They have to stay in jail forever.”

The murder has drawn widespread attention, including viral comment on #JusticeForJunior, $60,000 in GoFundMe donations and outraged tweets from Cardi B and Yankees pitcher CC Sabathia — who Saturday tweeted, “I’m a father of four and couldn’t imagine losing any one of my own kids. The violence and hate needs to stop.”

Additional reporting by Amanda Woods and Laura Italiano