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A day into one of the city's biggest murder investigations in decades — two men, two women and two boys shot and stabbed — police conceded Tuesday they had virtually nothing to go on.

Investigators said they believed the attacker or attackers were not among the dead, ruling out a murder-suicide.

But detectives faced a broad window for the killings: some time between Saturday night and Monday evening, when the six bodies and three wounded children were found in a small brick home on a dead-end street in a poor neighborhood east of downtown.

Officers went door to door looking for tips that could lead to a suspect or a motive.

"We're working with a blank sheet of paper," police spokeswoman Monique Martin said.

Most of the victims had been shot and at least one child had been stabbed, authorities said. The children ranged in age from about 1 to 12 years old, police said.

The surviving children were hospitalized, two in very critical condition and the other in serious condition, according to police. Their families asked that no details of their conditions be released, and it wasn't clear when or if they might be able to help investigators.

Meanwhile, authorities hoped for leads from the rough-edged community called Binghampton, where low-income houses and apartments sit near cheap motels and junkyards.

"We know there are people out there who have heard things, seen things, known things" that might help "put together pieces of the puzzle on what occurred in that home," said Lt. Joe Scott, a homicide detective.

The street where the killings occurred remained blocked off to bystanders and media Tuesday, the home cordoned off by crime-scene tape. A forensics van was parked out front.

Just down the street stand three cinderblock motels, one called the Pleasure Inn, all surrounded by privacy fences. Tough-looking dogs chained in the backyards of numerous residences sent up a stream of barks and howls.

The nearest major intersection boasts automobile salvage yards on all four corners, surrounded by chain-linked fences and razor wire.

It was not immediately clear how the killings could have gone unnoticed — police said five of the six victims were shot — though the neighborhood does experience some drug- and gang-related violence. Early Tuesday, as police investigated the six slayings, two men were shot and wounded in an unrelated home invasion about a mile away.

The weekend attack appeared to be the worst single shooting in Memphis in at least 33 years. In May 1973, a man with a history of mental illness randomly shot and killed five people, including a police officer, before he was killed by police.

More recently, a firefighter killed four people in 2000, including two other firefighters and a sheriff's deputy.

Even in a city accustomed to violence — last fall, the FBI ranked Memphis eighth in the country for reports of serious crimes per capita, though local law enforcement questioned the FBI's methodology — the killings stunned the neighborhood. About 30 residents gathered for a prayer service Tuesday morning at the First Baptist Church, where Pastor Keith Norman said the grandfather of one of the victims was a member.

"This is a breach in our community, and we as a church are the repairers of that breach," church member Cheri Wells said. "I feel a sense of vulnerability. I feel pain and hurt. I feel we have been robbed. Our peace has been snatched from us."

Wayne Bolden, who lives across the street, said the family kept to themselves but the apparent man of the house occasionally fired gunshots in the yard.

"He'd shoot on the Fourth of July and New Year's Eve," Bolden said. "He'd have company over and I'd hear the shots."

None of the victims had been identified. A phone number at the single-family home went unanswered Tuesday.

Rob Robinson, who owns the home, said the man who rented it lived there with his girlfriend and at least three children. Robinson estimated the man and woman to be in their late 20s.

"I would categorize them as good tenants. They kept the property and they called me when there were problems. They paid their rent on time. They were always very courteous and polite."

Robinson said the man had problems with a former girlfriend. "When I was over there, there were a lot of heated conversations over the phone," he said.

But he said he saw nothing to suggest the level of violence that took place.

"Not that this would ever be expected," he said, "but there wasn't a history there I had experienced that indicated this kind of activity or crazy things going on."

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