A suspected serial killer linked to multiple Virginia murders from nearly four decades ago is accused of killing two women who were found slain along a state parkway in 1986, according to the FBI. The FBI's Norfolk Field Office announced on Tuesday, January 20 that advancements in forensic technology and DNA evidence revealed Alan Wade Wilmer Sr., of Lancaster County, killed Cathleen Thomas and Rebecca Dowski. Thomas and Dowski's deaths are a part of a series of eight killings and disappearances, dubbed the "Colonial Parkway Murders," that unfolded on or near the state's Colonial Parkway between 1986 and 1989, according to a news release from the FBI. Wilmer, who died at age 63 in 2017, was previously connected to the killings of three victims: David Knobling, Robin Edwards, and Teresa Lynn Spaw Howell, authorities announced in 2024, NBC News reported. According to the FBI, Thomas, 27, and Dowski, 21, were with each other when they vanished in October 1986. They were ultimately found dead together inside their car along the parkway. 'Torso' Killer Confesses to Murder of 18-Year-Old in New Jersey: Police After a person jogging came across their vehicle, authorities discovered both women's throats were slit, The Virginian-Pilot reported. It also appeared that someone tried to light the car ablaze, according to the newspaper. "Despite extensive investigative efforts at the time, the case remained unsolved for decades," the FBI said. Breakthroughs in the case came with the help of forensic science as investigators continued to seek justice for Thomas and Dowski, according to the FBI. The women were in a romantic relationship and started dating months before they were killed, NBC News reported. The FBI described Thomas as "a vibrant young woman known for her compassion, intelligence, and close relationships with family and friends." The agency said Dowski "was a talented musician and college student with a promising future, remembered for her creativity, kindness and love of music." "Their lives were tragically cut short, but they were never forgotten by the investigators who continued to pursue justice on their behalf," the FBI said. Suspect in 1991 Austin Yogurt Shop Murders Linked to 1998 Kentucky Cold Case If Wilmer were still alive, the U.S. Attorney's Office for the Eastern District of Virginia said that he would have been federally prosecuted in Thomas and Dowski's deaths, according to the FBI. Cathleen Thomas' brother, Bill Thomas, told WTKR he was surprised when he heard the FBI determined Wilmer was suspected in his sister's death. "We've had 150 persons of interest in this case, and I was still surprised it was Wilmer," Thomas said to the TV station. "I always knew that was a possibility, but other suspects had sounded more likely somehow." The FBI continues to investigate other unsolved cases as part of the Colonial Parkway killings, the agency said. "Our message today underscores that we will not stop, we will not forget, and we will seek justice no matter how long it takes," Dominique Evans, special agent in charge of the FBI's Norfolk Field Office, said in a video shared by the agency on January 20. The Colonial Parkway is a 23-mile stretch of road that links Jamestown, Williamsburg and Yorktown.