CNN: Detectives are questioning two people in connection with the killing of a Gulf Coast couple known for adopting special-needs children, the Escambia County sheriff said Saturday.

Investigators have found a red Dodge van recorded on surveillance cameras leaving the Beulah, Florida, home of Byrd and Melanie Billings, who were found dead in their home Thursday, Sheriff David Morgan said.

"Interviews with associated neighbors, friends and family" led to a relative of the van's owner and another person, who were being questioned Saturday evening, the sheriff said.

No arrests have been made, and Morgan would not discuss whether the "persons of interest" had any connection to the Billings family. But the sheriff said investigators can tie the pair "to enough significant events and instances in this case that would lead a reasonable person to believe that they have an association with these murders."

A third person sought for questioning had not been found, Morgan said.

The Billingses died in what police are calling a home invasion, but investigators have not said whether the couple was robbed.

Eight children found at the home after the shootings are being cared for at an undisclosed location, Morgan said. The children, ranging in age from infant to about 11 years old, were not injured, police said.

Twelve of the Billingses' 16 children were adopted, some of them with special needs, the Pensacola News Journal reported.

Emergency personnel and police went to the home after receiving a call just before 8 p.m. Thursday about shots being fired, said Escambia County Police spokesman Sgt. Ted Roy. An employee of the couple found their bodies, Roy said.

Beulah is west of Pensacola, near the Alabama state line.

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