West Suburban Bureau

CBS 2's Mai Martinez contributed to this report.
ST. CHARLES, Mo. (CBS) ― Hundreds of people gathered in the suburbs of St. Louis Friday afternoon to remember Kimberly Vaughn and her three young children.

The bodies of the Oswego woman and her children were discovered on a remote road in Will County last week. All four had been shot to death - Kimberly once, her children multiple times.

As CBS 2's West Suburban Bureau Chief Mike Puccinelli reports, Kimberly's husband and the father of the children, Christopher Vaughn, was among the mourners who arrived under heavy security at the visitation. He was the lone survivor of the shootings.

Sources told CBS 2 Christopher was being monitored by police, partly so they could keep tabs on his whereabouts and also so they can protect him lest someone who doesn't necessarily believe his version of events decided to take the law into their own hands.

Police blocked one of the entrances while funeral home staffers talked with the driver of every vehicle that drove into the parking lot. Christopher arrived with a crowd of people and quickly made his way inside.

Missy Jones saw him at the memorial. While it was an unusual and terribly tragic scene, she said, she didn't believe it was particularly awkward for many mourners to be around the man who sources say has accused his wife of killing their children and shooting him before turning the gun on herself.

"People feel different, I guess," Jones said. "I don't know. People were approaching him."

It was a week ago Thursday that the bodies of Kimberly, 34, and children Abigayle, 12, Cassandra, 11, and Blake, 8, were found inside the family's sport-utility vehicle parked on a service road in Channahon Township.

Police were called to the scene by a passerby who was waved down by Christopher, 32, who was the lone survivor of the shooting and had been wounded by a gunshot to the thigh.

Illinois State Police have not said who they believe fired the fatal shots, and they are not calling Christopher Vaughn a suspect. But they have spent hours both talking to him about what happened and searching the family home in Oswego.

But police did not respond to questions about what they were seeking, but were seen taking computer hard drives, printers and cable boxes from the house on Wednesday.

CBS 2 Legal Analyst Irv Miller said on Friday the investigators reluctance to talk about their investigation does not necessarily reflect what they know.

"They know a lot right now," Miller said. "They probably don't have everything. They probably don't have toxicology back, but as far as knowing where the shooter was standing or sitting at the time by comparing entrance and exit wounds, they know that."

While witnesses told CBS 2 that Christopher Vaughn said his wife shot him and his children, one investigator reportedly told a friend he was skeptical of the claim given the angle of Vaughn's bullet wound.

The Chicago Tribune reported on Friday that Vaughn told police he did not remember what happened.

CBS 2 reported Tuesday night about an alleged relationship Vaughn claimed he'd confessed to his wife just before the shootings. The Chicago Sun-Times quoted a source Friday as saying he was considering divorce.

Investigators are hoping evidence taken from the Vaughn family home will yield more clues and answers in the case.

On Wednesday, investigators spent almost two hours in the Vaughn home, taking computer hard drives, printers and cable boxes.

Christopher Vaughn owned a computer company that specialized in computer security and because he is the only survivor, the equipment police removed on Wednesday is material and of particular interest to investigators.

"They're crossing their t's and dotting their i's. They're going through everything. Was there something on TV that gave him an idea that could've led to this thing happening?" Miller said. "They're talking to his friends to see, 'Hey am I getting a divorce? Am I unhappy with my wife? Boy wouldn't it be something if this happened or that happened."

If you look closely at a picture of Chris Vaughn taken by a Sun-Times photographer, a bandage is visible on his left wrist. A well-placed source tells CBS 2 it covers a wound made by the same bullet that tore through Vaughn's left thigh. Investigators think that also might be significant.

Miller said although police are not calling Christopher Vaughn a suspect, he believes they are looking at him in that capacity, and at this time, they are looking for any indication that he might be the person to tie the physical evidence in the case.

If that is true, it could lead to charges.

Regardless of the circumstances, at the memorial on Friday Missy Jones said the harsh reality of seeing a mother and her three young children in caskets next to each other was hard to take.

"There's not words to describe it," Jones said. "You know you just feel helpless. What can you do? We're just praying for them."

Many of the people in St. Charles were from the New Hope Presbyterian Church that Kimberly belonged to when she met Chris Vaughn while living in Missouri.

"She was a great person, an outgoing person," mourner Peggy Brown said, adding how difficult it was to say goodbye.

"It was very hard," she said.

Funeral services for the Vaughn family will be held Saturday at 1 p.m. at the New Hope Presbyterian Church in St. Charles, Mo.

CBS 2's Mike Puccinelli is there and will have updates.

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