PENSACOLA, Florida (CNN) -- A man police believe organized the slaying of a Florida couple earlier this month told authorities he knew the victims and received financial support from them for a martial arts studio, according to court documents released Monday.

Leonard Patrick Gonzalez Jr., 35, is one of seven people charged with murder in the July 9 killings.

Leonard Patrick Gonzalez Jr., 35, is one of seven people charged with murder in the July 9 deaths of Byrd and Melanie Billings of Beulah, Florida.

An affidavit for a search warrant for Gonzalez's van noted the connection between him and the couple, but gave no other details.

"My understanding is, through speaking with the investigative agencies, that Mr. Gonzalez sought donations from a variety of community and business leaders and that perhaps Mr. Billings did not lend him money, but donated to this academy for children," Crystal Spencer, attorney for the Billings family, told CNN. "It was a defense academy -- a self-defense academy for children. But the connection goes no further that we are aware of."

The Billingses, who were known for adopting special-needs children, were fatally shot during a home invasion robbery, according to police. Their bodies were found in their bedroom, said the court documents.

Gonzalez told police he owns a red Dodge cargo van similar to one seen on surveillance video leaving the Billings home on the day of the slayings, but he said it was not in operating condition, according to an affidavit seeking a search warrant on the van.

After a picture of the van seen at the crime scene was released to the media, a man contacted police to tell them it resembled a van he owned for a number of years and had recently sold to a woman named Terri Poff, the affidavit said. He provided pictures of the van, which appeared to match the one seen on the surveillance camera, including some of its unusual features, the documents said.

The man told police that Poff told him she was buying the van for her son, Leonard Gonzalez, according to the affidavit. Watch recap of the case and links between suspects »

Authorities located the van at Gonzalez's residence, and its vehicle identification number matched that provided by the previous owner, the documents said.

A search warrant document filed with the court shows that in a July 11 search of the van, police took carpet samples, seat covers, a piece of duct tape, paint samples, and containers of disinfectant wipes, garbage bags and soap pads, among other items, the document said.

Police previously have said robbery was a motive, but not the only motive.

Asked whether the slayings could have been a contracted hit, Escambia County Sheriff David Morgan told CNN, "This gets back to motive and we want to assure the public that we haven't taken that or anything off the table. We're looking for any reason, any motive for this to have happened, so yes, we are looking at a hit as a motive.

Morgan told CNN he wanted to talk to up to nine more people and planned to make at least one more arrest before he winds down the investigation in a few days. He did not provide further details, but said authorities planned to interview Gonzalez's wife on Monday.

The Billingses had adopted 13 children, and each had two biological children, but three of the adopted children have died. Police said nine of the children were home at the time of the home invasion; one of them managed to flee and seek help at a neighbor's home.

Ashley Markham, one of the adult children from Byrd and Melanie Billings' previous marriages, said she has decided to move into the home to take care of the children.

Markham told CNN that they are having work done on the home to make it safer before they move back in.

Additional documents released Monday from the Florida Department of Children and Families show a bizarre attempt by Byrd Billings to copyright the children's names and request money from the department for their use.

A department attorney, Katie George, told the Pensacola News-Journal that every time the agency sent Billings a letter referencing the children by name, he would reply with an invoice demanding millions in copyright infringement. In one document released by the department, he demands $10 million in silver or federal reserve notes of equal value.

In a sharply worded letter of December 2005, another department attorney, Richard Cserep, wrote to Billings, "you reference a wide variety of law in connection with this claim" for damages. "This includes copyright violations, trademark violations, contract violations, admiralty and maritime law, libel and the Truth in Lending Act. At no time in any of your correspondence have you made a plain demand for damages under a clear and cognizable theory of liability."

A handwritten note on the letter says that no further correspondence was received from Billings after that letter.

A safe containing prescription medication, family documents and some jewelry was taken from the Billings home at the time of their slayings, authorities said. It was found in the back yard of Pamela Wiggins, an eighth suspect, who is charged with being an accessory after the fact. Wiggins is free on $10,000 bond. Watch lawyer reveal contents of safe »

Morgan said when the safe was found, it was buried with bricks on top in "an obvious attempt to conceal" it. Wiggins is a friend and landlord of one of the suspects. Attempts by CNN to reach her and her attorney have been unsuccessful.

One of the seven original suspects in the case, Donald Ray Stallworth, was arrested in Alabama. At a hearing Monday, Escambia County, Alabama, Judge Bert Rice withdrew an earlier $1 million bond and ordered Stallworth held without bail until Alabama Gov. Bob Riley signs an order to extradite him to Florida.

Surveillance video from the home shows two vehicles pulling up to the property and five masked people dressed in black entering the house. Authorities believe both drivers remained in the vehicles.

It appears the suspects did not believe they were under surveillance, Morgan said. The system, which was not disabled, was a "gaping hole" in a well-executed crime, he said.

While the investigation into the murders continues, Markham said her focus now is on helping the rest of her family through the tragedy. She said she told the children about their parents, adding that her mother had explained heaven to the kids as a wonderful place.

The kids were given balloons and told by writing messages on them, they would be able to talk to their parents since "they were angels."

CNN's Susan Candiotti, Ross Levitt, Aaron Cooper, Mike Phelan, Ed Lavandera and John Couwels contributed to this report.

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