LYNN – In the fall of 1979, four separate murders occurred within weeks of each other that have haunted the family members of those slain and puzzled police officers for decades.The mystery begins with Susan (Caroll) DeQuina, a 22-year-old mother of two who vanished without a trace after she left to buy a refrigerator with her Hells Angels boyfriend and his friends. A web of secrecy follows her death, with the unsolved murders of Robert “Bino”Garbino, 22, of 126 Winnepurkit Ave., and Michel Gagnon, 27, a native of Quebec, both linked to the Hells Angels motorcycle group.A fourth victim, 15-year-old Paula Kallenback, of 16 Dell Court, disappeared in the same neighborhood within days of the other murders, but has not officially been linked with the ruthless gang.?We?re hoping, now that 30 years have gone by, that someone is willing to talk about what happened,” said Lynn Police Captain Mark O?Toole. “People talk for many different reasons, some out of guilt, others to get back at someone? but someone knows the details.”O?Toole has revamped efforts to get to the bottom of the cases, which have stumped a number of detectives over the years as the killer or killers continue to freely walk the streets.The murder spree began the night of Oct. 3, when rebellious DeQuina disappeared. Police say she left her young boys with a teenage next door neighbor so that she could pick up a new refrigerator with her boyfriend, Steve. At the time, the teen told police that the Baker Street apartment was filled with people when he arrived, people who were later found to be associated with the motorcycle gang.O?Toole said Steve?s real identity was determined to be Michel Gagnon, a member of the “Papeyer” motorcycle club, who had either become a full member or regular associate of the local Hells Angels. When Steve eventually returned to her apartment around 1 a.m., DeQuina was not with him and hasn?t been seen since.Police believe she was killed because she had threatened to report that vehicles she had been renting for the use of Hells Angels were being used to transport drugs. After she vanished, her car was found torched on Fairmont Avenue.?If she left home with several of her friends, someone has to know what happened to her,” O?Toole said. “She led a high-risk lifestyle and was in with a rough crowd. People out there know exactly what happened, but there is a climate of fear since organized crime is involved.”That fear has led to a dead end in tips over the years, leaving DeQuina?s sister, Kathleen and her family living a never-ending nightmare.?She got into a really bad crowd and when she wanted to get out, it cost her her life,” she said. “The sad part is that she went with people she trusted, thinking she was getting a refrigerator. It broke my heart because I saw the side of her that other people didn?t see.”Kathleen said her father, Richard, died during the effort to find his daughter and made her promise that she would keep the investigation alive.?Everyday for 10 years, he would go to her place on Baker Street, turn the light on and say, ?Sue, are you here??” she said. “I can feel that she?s somewhere close and the fact that we can?t find her makes me sick. If I had a map of areas that she might be in and a couple of dogs, I?d go out there looking for her myself.”While DeQuina?s body remains to be found, pieces of Garbino?s dismembered body were discovered scattered around the city following his murder on Nov. 4. A roommate of Gagnon?s, Garbino was savagely murdered in his home on Winnepurkit Avenue, where he was shot once in the shoulder and once in the head.In an attempt to disguise his identity, his attacker decapitated him, cut off both of his hands and sliced the tattoos off of his arms. His torso was then dumped in nearby vacant lot on Fairmont Avenue, while his head and hands were buried outside of his home. An alleged Hells Angels associate, Garbino was on his way to being designated as a “prospect.” According to O?Toole, while hi