the suburbs of Washington, D.C. Police looking for clues in three unsolved murders with striking similarities. And ABC's David Kerley has the evidence that may connect the dots. Reporter: It was broad... See More
the suburbs of Washington, D.C. Police looking for clues in three unsolved murders with striking similarities. And ABC's David Kerley has the evidence that may connect the dots. Reporter: It was broad daylight. A knock on the door. When the door was open, he started shooting. Longtime neighborhood piano teacher Ruthann Lodato killed. That was a month ago. And tonight, evidence her killing may be linked to two others, meaning a serial killer could be at work in this Washington, D.C. Suburb. The similarities and unusual nature of all three shootings occurring in Alexandria require the police department to consider possibility that all the cases are linked together. Reporter: The similarities? Lodato killed in February. In November, a local transportation official gunned down. And ten years ago, a real estate agent and wife of the sheriff also shot and killed. All three involved in their community, all gunned down in their homes in broad daylight. All three killed within two mi miles of each other. Police say there's forensics that show similarities in all three killings. The bullets have the same general characteristics and are similar in design. The search is intensifying for a suspect and a motive. He believes in his mind that these three people represent the city of Alexandria. And the city has wronged him. And he's going to make it right. Reporter: A bearded and balding white man is who they are looking for. They have a warning. Do not open your door to strangers. Reporter: A possible serial killer on the loose. David Kerley, ABC news, Washington.
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