Police say woman's slaying appears to be linked to 2 other unsolved deaths in Alexandria, Va.

ARLINGTON, Va. – The slaying last month of an Alexandria woman who was shot when she opened her front door appears to be linked to two other unsolved killings in the city, police said Thursday, leaving residents fearful and wondering if an unknown killer has been striking their community for years.

Forensic examination of bullet fragments found similarities among the ballistics in last month's shooting of music teacher Ruthanne Lodato, the Dec. 5, 2003, slaying of Nancy Dunning and the Nov. 11, 2013, killing of Ronald Kirby, Alexandria Police Chief Earl Cook said at a press conference.

Cook said the ballistics testing found similarities, but he could not state conclusively that the same weapon was used in all three shootings.

"The cases appear to be linked, but until we have evidence to point to only one suspect, we investigate all possibilities," Cook said.

In addition to the ballistic similarities, all three were killed at approximately the same time of day, in the late morning hours. Also, Cook said, all three were killed in their homes after presenting themselves at the front door. Cook could not say for certain whether the shooter knocked on the door in the other killings as he did in the Lodato shooting.

A second woman was wounded in the Lodato shooting. Police say they are looking for an older, white male with gray hair and a full beard.

All three victims were prominent in the Alexandria community. Lodato was a well-known music teacher, Kirby a respected transportation planner and Dunning a real-estate agent who was the wife of then-Sheriff James Dunning.

For years, Dunning was a suspect in his wife's death, and had not been ruled out as a suspect at the time of his death in 2012.

Asked about Dunning, Cook said at his press conference that it is standard procedure for police to consider family members as suspects in an unsolved slaying and no suspects are ruled out until an arrest is made.

Cook said the police are investigating the cases as though they are linked, but are not ruling out other possibilities.

No motive has been established in the killings, Cook said. He acknowledged the fear that the shootings have triggered in the community, given their apparently random nature. He urged residents to be vigilant and not to open their front doors to strangers, but not to overreact.

"I'm hoping it doesn't create any type of hysteria," Cook said.