(CNN) -- Four victims and the man who shot them were found dead at two homes located roughly nine miles apart in northwestern Wisconsin, authorities said.
Ritchie German, Jr., 33, has been identified as the deceased shooter responsible for the two crime scenes, said Chippewa County Sheriff James Kowalczyk at a Tuesday press conference.
Two others were injured by German, police said, and three juveniles and one adult survived the attacks unharmed.
Investigators believe German may have been trying to kidnap one of the victims, Kowalczyk said.
The chief likened the slayings to the kidnapping of Jayme Closs, whose parents were murdered during her abduction in Barron County. He speculated that the killer's motive in this case could be similar, although he offered no evidence to support the claim.
Police are trying to locate a permanent address or vehicle for the suspect, he said.
"A question is, what was his intention? Was his intention to take this young gal, similar to what happened in Barron County? And if so where are his belongings?" Kowalczyk said.
Describing the timeline, Lake Hallie Police Chief Cal D. Smokowicz said "the situation was over as fast as it started."
Dispatchers sent police officers to respond to an "unknown problem" at the Lake Hallie location on Sunday at about 10:22 p.m., said Smokowicz.
All was quiet when officers arrived at 10:28 p.m., he said.
Entering the house, police found two injured victims and performed life-saving procedures. Next, the officers found two people who were obviously dead and four other people hiding from gunfire in the home.
Police identified the deceased victim as Laile Vang, 24. German killed himself, police said. Investigators believe he may have been trying to kidnap her.
What were "his intentions, Kowalczyk asked, "in the event he was going to kidnap her rather than kill her?"
About four hours later three more victims turned up when deputies went to a home in the town of Lafayette to notify relatives of the Lake Hallie victim, Kowalczyk said.
Police identified the dead there as Bridget German, mother of the shooter, Douglas, brother of the shooter, and Douglas' son, Calvin, 8 years old.
"All three suffered gunshot wounds to the head. I assume they were killed instantly," said Kowalczyk.
Police do not know when they were killed but believe it happened Saturday morning, he said. German may have slept in the house with the dead bodies on Saturday night, he speculated.
About the shooter
For the past 15 or 16 years, German has been living off and on with his mother, police believe.
German came to the attention of police in 2004 because of an incident involving German, his mother and his brothers, police say. His mother called police to her home when her son threatened his brothers with a gun.
German was arrested for "endangering safety due to a firearm" and put on probation, said Kowalczyk. A few years ago, he received a traffic citation. "That was the only contact" police had with German, he said.
"I spoke to most of his siblings and most of them did indicate he was a troubled person," said Kowalczyk, who also described German as "a loner" who had no friends.
German had "no employment that we know of, no vehicle that he was operating other than his brother's and mother's. He kept to himself," said Kowalczyk.
Police recovered texts that were "sexual in nature" sent from German's phone to Vang, he said. German's motives for the shootings are not clear, he added.
An interview of Vang's parents was attempted and neither had heard of German, police said.
Vang's mother and father each suffered defensive injuries -- gunshot wounds -- and appear to have approached German to try and stop him, police said. Dispatch has a recording of a caller saying, "My father has just been shot," said Smokowicz.
Replaying that conversation, police can hear another shot in the background, he said. Both parents will recover, though each has had an arm amputated as a result of their injuries, police said.
Due to the seriousness of the incident, the investigation has been turned over to the Chippewa Falls Sheriff's Department, Smokowicz said.
'This is a shock'
The string of deaths has rocked the tight-knit community about 100 miles east of Minneapolis.
Barbara Potts, of Lake Hallie, told CNN affiliate WQOW that the killings have hit her neighborhood hard.
"Very shook up," Potts told WQOW. "I told the policeman, 'You never come here. You don't have to come on this street.' We're very quiet; everybody knows everybody. This is a shock."