"Joseph, this is Mom," Patricia Long said on the message left for Joseph Palczynski. "This is hurting all of us. Please, I don't know what to say anymore, and I don't want you killed.
"I know you said you'd kill yourself before you'd go back, and if you got to do it, then do it," she said before abruptly breaking off.
The search for Palczynski continued Friday as residents locked up their homes and schoolchildren were kept indoors.
Police have recovered guns they said were used in the shooting spree and a stolen car Palczynski was believed to have driven, but the 31-year-old apprentice electrician hasn't been found.
Authorities say Palczynski abducted his estranged girlfriend, Tracy Whitehead, on Tuesday night in nearby Bowleys Quarters after shooting George and Gloria Shenk to death. The couple had sheltered Whitehead after she moved from Palczynski's home a few days earlier.
Whitehead told police after she escaped; that the rifle and pistol grip shotgun were Palczynski's only weapons, but investigators weren't taking any chances.
"It's been 24 hours now. Who knows what he's got?" Baltimore County Police Spokesman Bill Toohey said Thursday.
Outside the Shenk home, he allegedly shot and killed David Meyers, 42, a neighbor who tried to help Whitehead during the struggle.
On Wednesday night, police said, Jennifer McDonel was fatally shot and a 2-year-old boy was wounded when they drove by as Palczynski fired shots during an attempted carjacking. The boy, shot in the cheek, was in stable condition.
Whitehead escaped late Wednesday after she and the suspect stopped at a motel in suburban Baltimore.
On Wednesday evening, before Whitehead escaped, police say Palczynski broke into 81-year-old Anna Etter's home, handcuffed the woman to her bed and stole her car.
"He asked if I'd call his mother when this is all over and tell her he loves her," Etter said.
According to court records, Palczynski has an extensive criminal history dating to 1988, including convictions for assault and battery.
In 1989, Idaho police use tear gas to flush him from an apartment while serving a warrant. The Washington Post, citing court documents, reported Friday that Palczynski was an escapee from a Baltimore County mental facility at that time, with a psychiatric diagnosis of bipolar disorder and a "homicidal and violent attitude."
Palczynski was arrested last Saturday for allegedly assaulting Whitehead. He was released a day later on bail, then bought a rifle and shotgun on Monday, court papers said.