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DEVELOPING: Police in Florida are seeking another person of interest in the home-invasion killings of a Florida couple known for adopting special needs children.

Escambia County Sheriff David Morgan identified the latest person wanted for questioning in the murders of Byrd and Melanie Billings as Pamela Laverne Long.

Long has several aliases and is currently in hiding or on the run, Morgan told reporters Wednesday, holding up a photo of her at a news conference. She is a realtor who is well known in the Gulf Breeze area near where the robberies and killings occurred in Pensacola.

Authorities want to talk to Long as a witness, he said. They have had no contact with Long for 48 hours, which has them "concerned," according to Morgan.

"Our intent is not to harass Miss Long. We need to speak to Miss Long," he said.

Morgan said it is significant that the surveillance camera was not disarmed at the time of the robbery, which he has described as "well planned" and "well executed."

Authorities believe it was someone's job to disable the equipment before the break-in was carried out, but that person failed to do so.

"The execution of the operation was flawless except for surveillance system," Morgan told reporters. "Why was sytem left on in an otherwise perfectly executed murder?"

He said detectives have outlined at least one other person of interest in addition to Long.

He said authorities have all seven of the men who robbed the Billings home and killed the couple in custody, classifying the murder as "solved."

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A band of men charged in the home-invasion killings of a wealthy Florida couple known for adopting special needs children trained for a month to rob them, investigators said Wednesday.

Byrd and Melanie Billings were shot to death at their sprawling home near Pensacola last week by several intruders caught on surveillance cameras, some wearing what police described as ninja garb.

The robbers entered from the front and rear and left within 10 minutes.

Seven men, including day laborers and an Air Force staff sergeant, are jailed in the case on charges including murder, and detectives say there is an eighth arrest coming.

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Investigators say the robbery was extremely well orchestrated.

"It was a very well-planned, thought-out, methodical operation," Escambia County Sheriff David Morgan told "FOX & Friends" on Wednesday.

What is mystifying about the case, he said, is that none of the men were close friends or knew each other well — other than the father and son pair in custody. Two of the men had done some work at the Billings house in the past, but nothing extensive, he said.

Morgan told the CBS "Early Show" that investigators believe the group trained together for at least a month before the attack.

Morgan said investigators had "verified yesterday that this team, this group of people, had been in training at least 30 days, a month, prior to the execution of it at the Billings' compound."

Morgan said investigators believe they know who shot the couple but he declined to give more details.

"We have identified, in fact, who participated or I should say was the active shooter in this case. We've been asked not to release that at this time," he told CBS.

The couple had 17 children — four biological and 13 adopted. Nine children were at the home when the Billingses were killed. Three saw the intruders but were not hurt.

The suspects arrested since the weekend range in age from 16 to 56. Several were day laborers who knew each other through a pressure washing business and an auto detailer they worked for. One, Donnie Ray Stallworth, was with the Air Force Special Operations Command with an aircraft maintenance squadron at Hurlburt Field near Fort Walton Beach. It wasn't clear how he knew the others.

Stallworth had been deployed to Iraq and Afghanistan five times since 2002, an Air Force spokesman said.

Authorities have said the suspects, some dressed as ninjas, stole a safe and other items during the break-in Thursday. They would not say what was in the safe or what else was taken.

Some of the masked men entered through the front door, while others slipped in through an unlocked utility door in the back. They were in and out in under 10 minutes. The crime was captured by an extensive video surveillance system the Billings used to keep tabs on their many children.

Morgan has called 35-year-old suspect Leonard Gonzalez Jr. a "pivotal person" in organizing the crime, but stopped short of identifying him as the mastermind. He is charged with murder and read a statement in court Tuesday proclaiming his innocence.

His father, Leonard Gonzalez Sr., 56, was charged with evidence tampering after authorities said he tried to cover up some damage on a red van seen on surveillance video pulling away from the house. Officials said the damage was unrelated to the crime.

Day laborer Wayne Coldiron, 41, is charged with murder. He sometimes worked for a pressure washing business owned by the elder Gonzalez.

The other suspects arrested were Gary Sumner, 31, a day laborer, 19-year-old Frederick Lee Thornton, and a 16-year-old whom officials are not naming because he is a minor.

State Attorney Bill Eddins said he would seek first-degree murder indictments from a grand jury against all the suspects, including Gonzalez Sr. He would not say whether he will seek the death penalty.

Escambia County Judge Tom Johnson refused to set bail for the younger Gonzalez and Coldiron at the request of State Attorney Bill Eddins. Johnson set their arraignments for Aug. 6. Bond for the elder Gonzalez had already been set at $500,000. The other suspects were due in court this week except for Stallworth, who must be extradited from Alabama, where he was arrested.

The Associated Press contributed to this report.