The area near George Mason Elementary School was swarming with Alexandria police, some from the tactical unit and some from the canine unit after two women were shot at a home nearby on Thursday. (Michael S. Williamson/The Washington Post)

(Update: Police look for gunman, clues in fatal shooting in Alexandria)

The bearded, balding man knocked on the door about 11:30 a.m. Two women, a music teacher and a caregiver, opened up the home to the unexpected visitor.

The man — a stranger to the women, it seems — started shooting. In broad daylight, in the middle of a quiet Alexandria neighborhood, the music teacher lay fatally wounded, the caregiver shot but expected to survive.

On Thursday night, the killer was still on the loose.

“We are concerned,” Alexandria Police Chief Earl L. Cook said. “And the citizens should be concerned.”

Police identified the slain woman as Ruthanne Lodato, 59, who lived in the home in the 2400 block of Ridge Road Drive. Friends and colleagues described her as a dedicated music teacher who led classes for nearly two decades.

“She changed a lot of kids’ lives teaching that long,” said Kelly Cronenberg, who taught with Lodato in a program called Music Together Alexandria. “So many children.”

The killing — Alexandria’s first of the year — sparked equal parts fear and bewilderment in North Ridge, the neighborhood of single-family brick homes where it occurred.

“This is a tragic situation, and the whole area is shocked and saddened,” said Ken Hill, president of the North Ridge Citizens’ Association.

Detectives were left with a chilling concern: Could Thursday’s shooting be connected to the equally mysterious and high-profile slaying of prominent regional transportation planner Ronald Kirby, who was shot inside his home nearly three months ago? Authorities have said that there were no signs of forced entry at Kirby’s house, and his wife has said nothing was stolen. Police have not made an arrest. Kirby, 69, lived a little more than a mile from Ridge Road Drive and was killed sometime between 10 a.m. and 12:30 p.m. on Nov. 11.

“Obviously, that occurs to us,” Cook said of the possibility that there might be a connection between Kirby’s and Lodato’s slayings. “We will have to look to see those similarities.”

Thursday’s shooting sparked an extensive manhunt. Officers fanned through the neighborhood looking for the gunman, who police described only as an older, balding white man with gray hair and a full beard. Police dogs were employed on the ground, and a Fairfax County police helicopter flew above. Several schools were placed on lockdown.

One neighbor said police told her that the shooter wore a suit.

Cook said investigators did not know of a motive for the shooting, but he said they had “no indication at this time that [the victims] knew the suspect.” He said three people were home when the shooting occurred. He identified the surviving victim as a caregiver who worked there but did not provide her name or say for whom she provided care. He also declined to provide information about the third person in the house.

Cook said investigators had talked with the wounded woman, who remained in a hospital Thursday evening, but he declined to detail what she told them. He also declined to say what type of gun was used and offered only a brief description of what happened.

“The suspect knocked on the door and shot the victims when they answered,” he said.

Those who knew Lodato said that she came from a prominent family with deep roots in Alexandria. Barry Mudd, a neighbor, said that Lodato’s father was the late George Giammittorio, a judge on Alexandria’s Circuit Court. One brother, he said, is retired Alexandria General District Court judge Eugene Robert Giammittorio, another brother is a securities lawyer in McLean and a third is a physician based in Alexandria.

Mudd said that Lodato’s husband, Norman, was active in the North Ridge Citizens’ Association.

Mudd said he recalled seeing Lodato and her elderly mother enjoying an afternoon outside in the spring. “They were sitting out on their stoop in rocking chairs,” he said. “It’s always good to warm your heart to see them there.”

Hill, the president of the North Ridge Citizens’ Association, said that Norman Lodato was a past president of the group and that he and his wife were known for their “sense of civic responsibility.”

Alexandria Mayor William D. Euille issued a statement extending his condolences to the family and expressing confidence that police would “work swiftly to apprehend the person who committed this horrible crime.”

“This is a sad day in the City of Alexandria,” he said.

Ruthanne Lodato graduated with a bachelor’s degree in music education from the University of Richmond, according to a résumé she posted online. It said she received a master’s degree in piano pedagogy from Catholic University.

Hill said Lodato taught hundreds of young children to play the piano over the years.

Melissa Jarvis, who taught with her at Music Together, said Lodato was a talented organist who played at weddings and funerals. “I’ll miss her,” Jarvis said. “She was a lovely woman.”

Nothing in Lodato’s background, friends said, seemed to provide clues as to who might want to hurt her.

Tim Battle, who has known Lodato since both were teenagers, said she was not the type to have enemies. “It’s a terrible thing,” he said. “If you had to name one of the nicest couples, the best people with the nicest kids, it would be them.”

Battle said Lodato had three daughters, the youngest still in college.

John McCrary, director of music at Blessed Sacrament Catholic Church in Alexandria, said he saw Lodato as recently as Wednesday night, when she came to the church to rehearse. She was supposed to perform at a choir event later this month, McCrary said.

“There are a lot of people in church right now praying for her,” he said.

Cook, the police chief, advised residents Thursday night to keep their doors locked and check to see who was knocking. But he acknowledged that, in a situation like the one Lodato faced, there was only so much any person could do.

“Hopefully,” he said, “you know the person at the door.”

Justin Jouvenal and Jennifer Jenkins contributed to this report.

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