"This is one of the most brutal cases this department has ever handled," a police spokeswoman tells PEOPLE

Accused Killer of Six Blames Meth in 'Vicious' Slayings: 'Don't Use Drugs,' He Allegedly Told Police

As he was escorted to an Alabama jail, Derrick Dearman told a crush of reporters that “drugs [were] making me think things that’s not really there” during Saturday’s slayings, according to the AP.

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Dearman said he turned himself in to authorities in Mississippi after sobering up and realizing “what was the right thing to do.” He also said the five victims were his “friends” and that there “are no words” to express the pain he’s feeling.

Dearman allegedly used an ax and a number of firearms to kill his victims, PEOPLE confirms.

According to Lori Myles, a spokeswoman for the Mobile County Sheriff’s Office, Dearman allegedly told investigators he went Saturday to the Citronelle, Alabama, home where his estranged girlfriend was hiding. Police said he was allegedly wielding an ax later used in killing five of her relatives – including a pregnant woman.

Police said that Dearman’s girlfriend, Laneta Lester, told them she had suffered physical abuse at her boyfriend’s hands, and had gone to stay with relatives to plan out a breakup.

Myles tells PEOPLE that, after his arrest, Dearman allegedly told police he’d been smoking crystal meth just prior to the attacks.

As officers were transporting him to jail, Myles says, Dearman allegedly kept repeating the phrase “don’t use drugs” before allegedly telling officers he didn’t deserve to be alive.

“This is one of the most brutal cases this department has ever handled,” Myles tells PEOPLE. “It’s mind-boggling. Typically, I go to every crime scene, but I didn’t this time. I didn’t think I would’ve been able to show up to work on Monday if I had seen some of what our detectives are now dealing with.”

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Several hours before the killings, police were called by one of Lester’s relatives, who had allegedly spotted Dearman outside the house, walking around the surrounding property. Officers were dispatched to the home but Dearman had allegedly fled the area by the time they’d arrived.

Later, after the sun went down, Dearman allegedly returned to the home, where he attacked the people inside as they slept, according to a sheriff’s statement obtained by PEOPLE.

The five victims and the unborn child were killed with “firearms and several other weapons,” according to the statement.

After the killings, police said Dearman allegedly kidnapped Lester and a 3-month-old baby whose parents had just died. Dearman then allegedly drove Lester and the infant to his father’s home just beyond the Mississippi state line, police said. That’s where Dearman allegedly freed Lester and the infant before turning himself in to the Greene County Sheriff’s Office in Mississippi.

Dearman said Monday he spared Lester and the child because “I came down and realized what was really going on,” according to the AP.

He has since been charged with six counts of murder.

As Dearman was turning himself in, Lester brought the infant to the police station in Citronelle, where she told authorities what happened, police said.

Police identified the victims as Robert Lee Brown, 26; Shannon Melissa Randall, 35; Chelsea Marie Reed, who was 22 and five-months pregnant; Justin Kaleb Reed, 23; and Joseph Adam Turner, 26.

A 4-month-old boy also survived the attack and was found in the home after the killings, police said.