"That house just has a sketchy vibe to it," the neighbor, who asked not to be identified, says.
Authorities went to check out the residence after receiving a 911 hang-up call at 11:30 p.m. When they arrived, they heard moaning inside the home and forced entry. Inside they found the five victims, all of whom had been stabbed to death, as well as a 13-year-old girl who was taken to a nearby hospital in critical condition. That child recently came out of surgery and is in serious but stable condition. Another 2-year-old girl was found in the home unharmed.
Two brothers, 18-year-old Robert Bever and his 16-year-old brother, who are related to the victims, were arrested in connection with the murders after police spotted them running out of the quarter million-dollar house's back door as they arrived on the scene. Police are not naming the younger brother as he is a minor.
A K-9 officer pursued them through the woods and they were successfully taken into custody an hour after the 911 call came in. Neither of the brothers have been charged with any crime at this time. One of them was later taken to the hospital, though police have not said why, the source tells PEOPLE.
Altogether, nine people lived at the home – two parents and seven children, four boys and three girls. Both parents, David Bever, 52, and April Bever, 44, are dead, as are two of the boys, ages 12 and 7, and one of the girls, age 5. The victims were all found in different areas of the home, authorities said in a briefing Thursday.
Police have not yet established a motive in the killings. However, multiple knives and hatchets were recovered from the home, Broken Arrow police Cpl. Leon Calhoun said at Thursday's briefing, Tulsa World reports.
"It's almost impossible to get your head around," he said.
A Sheltered UpbringingWhile the community was left shocked by the brutal violence, the neighbor tells PEOPLE that something hasn't seemed right with that family for a long time.
"They're very reclusive," the neighbor says. "The kids don't come out of the house."
She adds: "It's a very big house, but I've only ever seen a boy once and they've been here for many, many years. We only really knew they had kids because they have a pool and there are toys outside. But they don't come out."
The neighbor says the kids were homeschooled by a married couple who kept the children "on a very short leash."
"It's weird because they're old enough to drive," she says of the detained brothers, "but I've never seen them. And I've never seen a friend come to the house at all."
She continues: "They never open the blinds. The windows are never open.
"It's very scary."
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