Two Held on Murder Charges in Killing of Fla. Parents

This 2005 picture shows Byrd and Melanie Billings with their children, 10 adopted and two...

This 2005 picture shows Byrd and Melanie Billings with their children, 10 adopted and two biological, at their home in Beulah, Fla. Melanie is holding a photograph of their late child, Bailey. Investigators asked the public to be on the lookout Friday, July 10, 2009, for a red van they believe carried three men involved in the deaths of the Florida Panhandle couple who were shot in their rural home while eight of their children slept.

(The Pensacola News Journal, Karena Cawthon/AP Photo)

A statement on the Escambia County Sheriff's Office said officials sought three white males spotted in the van, though police would not specify the suspects' gender in later comments.

Escambia County Sheriff David Morgan said Saturday evening that tips from the public helped police find what they believed was the same van and its possible occupants.

"We are currently now are interviewing two persons of interest," Morgan said. "But again, the investigation, at this point, has been tied to the van that's in question."

Morgan said the rapidity of the crime and the video of the van suggested that the killers were experienced.

"It suggests experience to me," the sheriff said, "the rapidity of this crime -- in and out" of the couple's home.

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But, he added, police "have yet to determine a reason for, specifically, why the Billings were targeted."

Police found the Billings' bodies shot multiple times after they were summoned to the sprawling house in a rural area shortly before 8 p.m. Thursday.

The well-to-do Billings raised adoptees, many born to drug-addicted mothers and some with Down syndrome, along with their four biological children from previous marriages, according to reports.

Several children -- police were quoted saying there were eight ranging in age from 8 to 14, while Markham said there were nine children living at the home ranging from 3 to 11 -- were found unharmed inside the house, some of them still asleep, authorities said. Police reportedly were responding to a 911 call by a neighbor.

Markham and the Billings' daughter, Ashely, who is married to Markham's brother, said they were certain no Billings kids were connected to the crime, and that there were no additional family members home at the time of the killing.

'Mommy and Daddy Got Shot and Killed'

The Billings owned several local businesses, including a finance company and a used car dealership, The Associated Press reported.