DNA evidence and phone records put a 22-year-old Chicago man at the scene of a massacre of six Gage Park family members — an attack that started as a robbery, police said Thursday.

The details came as police announced charges against that man, Diego Uribe, and his girlfriend, Jafeth Ramos, 19. Each is charged with six counts of first-degree murder for the February slayings at the bungalow in the 5700 block of South California Avenue, authorities said.

Uribe is a nephew to one of the victims, Maria Herminia Martinez. Both he and Ramos allegedly gave statements implicating themselves to authorities.

Uribe and Ramos had planned to rob the family. The break in the case came when DNA evidence came back Wednesday linking him to the crime scene, as did Uribe’s cellphone records.

After he entered the home, Uribe confronted Maria Herminia Martinez on the first-floor of the home. Then they went upstairs. There, he shot her and then systematically beat and stabbed the other family members as he encountered them throughout the home, police said. Ramos was an “active participant” in the killings but did not shoot or stab any of the victims, police spokesman Anthony Gugliemi said.

There was already bad blood between Uribe and Maria Herminia Martinez, because the young man didn’t approve of her personal life, authorities said, although this wasn’t the primary motive.

The couple took a few hundred dollars, an Xbox and other valuables, police said.

In March, police gathered DNA evidence from Uribe and other family members as a routine part of the investigation.

Testing of DNA evidence came back showing it was Uribe’s blood that was found in the home, police said.

It took police 16 hours to process the crime scene for evidence, Chief of Detectives Eugene Roy said at a news conference Thursday, as he praised the team that investigated the case.

Ramos and Uribe were arrested Wednesday at the home they shared with Ramos’ parents, Cmdr. William Dunn said.

The pair had apparently continued on with their daily lives in the months after the killings and did not attempt to flee, Dunn said. Dunn did not know what Uribe intended to do with the money or why he allegedly decided to seek it from his aunt.

Chicago Police had long believed multiple killers were involved in the slayings.

Noemi Martinez, a relative of the family, said soon after the news of the arrests broke that she had heard of the charges in the case but didn’t know any details.

“Of course we’re happy,” she said. “We have been living in fear.”

Neighbor Martika Williams sat on her front stoop, relieved to know that police had caught the killers, but shocked at the identity of the suspects.

Uribe was a frequent visitor to the house, and a favorite of his young cousins, recalled Williams.

“[Uribe] played with those kids all the time. That family loved him,” she said. “This is not no random thing. This is someone that loved them kids, and those little kids loved him.”

In the days after the killing, Williams took care of the lone survivor of the Martinez household: the family pet, Pelusa, a shaggy mutt whose name is Spanish for “fluff.”

“I was concerned and I didn’t want to just give the dog over to no one, so the police asked me who in the family would I give it to,” Williams said, frowning. “And that was the first name I gave them: Diego.”

Police said Uribe had agreed to pick up the dog, but Williams said two women showed up to pick it up.

“I said I didn’t know them, and where was Diego,” she said. “I called his mom, and she said it was fine. He had a work thing he couldn’t get out of, and he was going to pick the dog up from them.

“That dog was already scared and upset. And I had no idea I was giving it over to the person that just killed its whole family in front of it.”

Supt. Eddie Johnson said the murders — a violent attack targeting a quiet, close-knit family, with victims ranging in age from 10 to 62 — shocked and frightened the Gage Park community and haunted police.

“For Chicago police officers and detectives, it became personal,” Johnson said. “The Martinez family weren’t repeat offenders or involved in any illegal activity. They were a family like any other, they went to work, they went school, loved each other and abided by the law.”

“I haven’t seen a case that has hit home as much for myself and so many others in this department as what was discovered on that cold day in February.”

The bodies of four adults and two children, ages 10 and 13, were found throughout the bungalow on Feb. 4 after a friend of Noe Martinez Jr., one of the victims, tipped police that the O’Hare Airport window cleaner hadn’t shown up for his job for two days.

Maria Herminia Martinez, whose body was found in a kneeling position in an upstairs bedroom, was shot four times in the head and in each of her hands. A source claims she may have been the main target. Martinez’s 13-year old son, Leonardo Cruz, suffered a dozen knife wounds. Noe Martinez Sr., 62, suffered 42 knife wounds all over his body. His wife, Rosaura, 58, had been stabbed in the abdomen five times. Alexis Cruz, 10, had been stabbed repeatedly, including three times in the heart.

The arrests in the case were first reported by Chicago Sun-Times columnist Michael Sneed.

Cook County court records don’t show any prior adult charges involving Diego Uribe. Ramos was arrested by the Cicero police on Oct. 6, 2015, for allegedly shoplifting and was released on a $1,500 bond, court records show. A warrant was issued for her arrest when she didn’t appear in court.