A series of vicious and shocking attacks carried out decades ago have been solved, thanks to DNA evidence.

Police in Aurora, Colorado, announced Friday they had identified a suspect in a 34-year-old set of cold cases involving the gruesome murders of a family and grandmother.

“This case haunted the officers who responded that night,” Aurora Police Chief Nick Metz said at a press conference. “It was a case that haunted the families and the victims to the core.”

The Denver Post reports the target of the investigation is a 57-year-old man already in prison: Alexander Christopher Ewing, who’s behind bars in Nevada on a 40-year sentence following a terrifying string of crimes.

Ewing is facing multiple counts of murder charges for allegedly killing three members of the same family in Aurora and a grandmother in the Denver suburb of Lakewood.

The breakthrough comes after a prosecutor in 2002 secured a John Doe arrest warrant in connection with the deaths of the Bennett family using DNA evidence. The prosecutor at the time charged the then-unknown individual with 18 counts.

Years later, in 2010, a detective provided DNA found from the murder of Patricia Louise Smith in Lakewood.

State forensic scientists were able to link the two DNA samples.

Then several weeks ago, the state of Nevada submitted Ewing’s DNA to a national database, which triggered a match with the two cases.

The match, Metz said, “sent a chill through my spine.”

Court documents show Ewing is facing a litany of charges in the Aurora family slayings, including three counts of first-degree murder, three counts of felony murder, attempted murder, first-degree assault with a deadly weapon, sexual assault of a child, two counts of sexual assault using physical force and first degree burglary with a weapon.

Formal charges are expected to come next week in Smith’s killing from January 1984, when a man entered her home, bludgeoned her and then sexually assaulted her.

Six days after the Smith attack, a man with a knife and hammer entered the Bennett’s Aurora home while they were celebrating the birthday of daughter Melissa.

The intruder clubbed Bruce Bennett and slit his neck. Debra Bennett was raped and beaten with a hammer.

The killer then raped and bludgeoned Melissa. The lone survivor was her 3-year-old sister, Vanessa, whom the killer beat in the head.

A relative came to the home the following day and discovered the gruesome scene.

“We’ve never forgotten this case. We’ve never forgotten these families,” Lakewood Police Chief Daniel McCasky said. “Hopefully, this begins a sense of healing, a sense of peace and sense of justice.”

Days before the slayings, a man had broken into the home of James and Kimberly Haubenschild and beat them with a hammer. Both survived.

That same day a man assaulted a woman in her garage with a hammer, which left her in a coma.

Months later, Ewing attacked a man in Arizona using a boulder. He was arrested but soon escaped custody, and while on the lam, Ewing snuck into a home and attacked a husband and wife with an ax handle.

Authorities launched a wide-scale air and ground search for Ewing, who was apprehended two days later and convicted in 1985.

As for the Colorado killings, authorities have started the extradition process to move Ewing from Nevada to Colorado. It’s possible he could face the death penalty, according to the newspaper.

“Today represents the first public and formal step in what will prove to be a long journey toward justice in this case,” Arapahoe County District Attorney George Brauchler said.

[Feature Photo: Alexander Christopher Ewing/Nevada Department of Corrections]