Last Updated 1:50 a.m. EDT.
Two men were held late Sunday on open murder charges in the slaying of a wealthy Florida Panhandle couple known for adopting children with developmental disabilities.
Day laborer Wayne Coldiron turned himself in to Escambia County authorities and Leonard P. Gonzalez Jr. was arrested in neighboring Santa Rosa County, Escambia County Sheriff David Morgan said.
Earlier Sunday, 56-year-old Leonard P. Gonzalez Sr. was charged with evidence tampering. Police said he tried to paint over and hide damage on a red van that was spotted on surveillance video leaving the home where Byrd and Melanie Billings were shot to death Thursday while eight of their children slept.
Coldiron, who was known to work with area car dealers, was friends with the elder Gonzalez, Morgan said.
More arrests are expected.
The Billings were killed in their spacious, nine-bedroom home in a rural area west of Pensacola near the Alabama state line. The house had an extensive surveillance system that authorities said captured three apparently experienced criminals swiftly slipping into the house before leaving and driving off in the red van. 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, though the companies the Billingses owned included a used car dealership.
"We are very anxious to share this story ... it's going to be a humdinger, I'll tell you that," he said earlier in the day.
Officials still haven't said why the family was targeted. Police also have not said whether anything was stolen from the home, which had nine bedrooms to accommodate the large family. The children who were there during the killings, ages 8 to 14, were interviewed by police and are now staying with other family members.
"Motive and motives in this investigation are still being developed," Morgan said after announcing the arrests of Coldiron and the younger Gonzalez.
The Billings had 16 children, 12 of them adopted.
They married 18 years ago and each had two children from previous marriages. They eventually started adopting children with developmental disabilities and other problems.
The house was carefully designed to accommodate the children, according to a 2005 story in the Pensacola News Journal. A camera was in every room, and the driveway was long to keep the kids from running into the street. A large swimming pool behind the house was gated.
The couple told the newspaper they wanted to share their wealth with children in need, but didn't imagine their family would grow so large.
"It just happened," she told the newspaper. "I just wanted to give them a better life."
Coldiron was expected to appear in court Monday. Because the younger Gonzalez was arrested in a neighboring county, he will have to appear there first.
They were charged with open murder because the investigation is ongoing and more charges may be added, Morgan said.
Bond for the elder Gonzalez was set at $250,000. A message seeking comment was left at a phone number listed for him in the Pensacola area.