DES MOINES, Wash. — A man who prosecutors say has “a consistent history of unprovoked attacks on unsuspecting strangers” is now charged with murder after beating a 69-year-old woman to death in Des Moines, according to charging documents.

Jake Berman, 39, is accused of repeatedly punching Marla Knigge, 69, and then stabbing her in the neck with a pair of tweezers at the door of her home in Spyglass Condominiums at 21937 7th Ave South in Des Moines on Aug. 4.

Prosecutors filed a second-degree murder charge against Berman on Friday after the medical examiner officially ruled Knigge’s death a homicide and DNA evidence from the tweezers was matched to Berman.

Investigators believe Berman attacked Knigge as she arrived at her apartment after a trip to a nearby store.

Police quickly became suspicious of Berman, whose mother lives one floor above Knigge.

Berman was the suspect in a violent attack on a 72-year-old man who was punched and kicked during a robbery two weeks earlier in the same area, according to a police report.

“As I continued to review Jake’s history, I discovered that he has a tendency to prey on unsuspecting victims,” ​​Des Moines Police Detective Brian Flynn wrote in an arrest report.

2024 incidents involving Jake Berman in Des Moines (from police reports):

• August 4th – the fatal attack of Marla Knigge
• July 21 – 72 years old beaten and robbed on 6th Ave in Des Moines
• April 21 – Domestic violence incident prompting SWAT response
• April 9 – Assault on guests in Spyglass Condos parking lot
• February 5 – Assault on a customer at the Safeway on Pacific Highway South

On the night of Knigge’s murder, Detective Flynn asked Berman’s mother if she could talk to him.

“I told (Berman’s mother) that the investigation into the attack on her neighbor (the July 21st assault and robbery) was active and ongoing and that her son, Jake, had been identified as a person of interest,” Flynn wrote. “(The mother) seemed shocked and stated that Jake is always home and never leaves the residence. (My mother) refused my requests to have Jake speak to me about his involvement in person or on the phone.”

The next day, on August 5, Flynn obtained an arrest warrant for Berman in connection with the July 21 attack. Des Moines police responded to Spyglass Condominiums and arrested Berman, noting in a report that he had “new injuries” to his fingers and hands.

Police took Berman to the jail for booking, but a nurse said Berman’s hand injuries were too severe for him to be booked. The jail nurse noted that Berman claimed he “struggled with the officers prior to the arrest,” but officers said that was not true.

“Jake did not struggle with the officers during the arrest, but the jail nurse’s observations further strengthened my belief that Jake’s hand and leg/ankle injury appeared fresh and resulted from some sort of assault,” Flynn wrote.

Investigators executed a search warrant for the Bermans’ apartment and found bloody clothing as well as dried blood on the doorknob leading to the hallway, according to the report.

On Aug. 8, prosecutors charged Berman with robbery in the July 21 case, and he was booked into the King County Jail.

On October 21, the Washington State Patrol crime lab reported that DNA from the forceps stuck to Knigge’s neck matched Berman. That same day, the King County Coroner ruled the death a homicide.

Berman was in custody when he was charged with the murder on October 27. He remains in custody on $2 million bail and is scheduled to appear in court for an arraignment on Nov. 7.