Wayne Coldiron, Leonard Patrick Gonzalez Jr. and Leonard Patrick Gonzalez Sr. are charged in connection with the killings of Byrd and Melaine Billings, who were found shot to death on Thursday. (Escambia Sheriff's Department/Associated Press)

Investigators are looking at business ties, among other leads, for a motive in the slaying of a wealthy Florida couple who adopted 12 children with developmental disabilities and other problems, authorities said Monday.

There may be multiple motives and more arrests are possible after three men were jailed Sunday, two of them on murder charges, in the shooting deaths of Byrd and Melanie Billings at their sprawling home near Pensacola, Escambia County Sheriff David Morgan said.

"It began as what we thought was a home invasion. At this point because of the complexity and the ties this family had through the business community, we're moving many other directions. Could be money, could be a whole host of things," Morgan said on the NBC show Today.

Morgan also cited the family's business ties in an interview on the CBS Early Show but declined to be more specific. He said investigators are working on "multiple motives."

Byrd Billings, 68, and Melanie, 43, owned several local businesses, including a finance company and a used car dealership.

Three men arrested in connection with the slayings were scheduled to appear in court Monday and Tuesday.

Day labourer Wayne Coldiron, 41, turned himself in to Escambia County authorities and Leonard P. Gonzalez Jr., 35, was arrested in neighbouring Santa Rosa County. Both were charged with murder and home invasion, according to their arrest warrants. The two were set to have a first court appearance Tuesday.

Authorities also jailed Gonzalez's father, Leonard P. Gonzalez Sr., on a charge of evidence tampering. Police said the 56-year-old tried to paint over and hide damage on a red van that was spotted on surveillance video leaving the Billings's home after the shootings Thursday. Gonzalez was due in court Monday.

Children with friends, family

The Billings had 16 children, 12 of them adopted. Eight of the children, ages 8 to 14, were in the house when the shootings took place on Thursday.

Ashley Markham, an adult daughter of the Billings, said the adopted children are together with friends and family at an undisclosed location. The Pensacola News Journal reported that Markham told a news conference Monday that she planned to carry on with her parents' legacy.

Asked about the three men arrested, Markham said she had no knowledge of any connection between those men, her parents or any of the children in the household.

"The people who have been arrested, we have no knowledge of them," she said. "That's all I know."

The Billings were well-respected in the area for providing a home for children with autism, Down syndrome and other developmental problems, and "especially Melanie has been referred to as an angel," the sheriff told CBS.

The surveillance video shows three armed, masked suspects arrive in the van, enter the house and then return to the vehicle, the warrants said.

The Billings's nine-bedroom home in a rural area west of Pensacola near the Alabama state line had an extensive surveillance system that authorities said captured the break-in. Tips from the public led police to the van Saturday.

Morgan said the investigation involves a complex web of relationships between suspects, though he declined to elaborate on them. He said it did not appear that the suspects knew the victims. The younger Gonzalez and Coldiron are friends, the warrants said.