BROOKSHIRE, Texas -- A person of interest was questioned for hours Friday about a double slaying in Brookshire, KPRC Local 2 reported.

Brookshire police said Stanley Jackson, 50, and Janella Edwards, 41, were shot to death at a home in the 3200 block of Third Street on Thursday. They suffered gunshot wounds to the head, detectives said.

"They're so sweet," Brookshire resident Mary Davis said. "They didn't bother nobody."

The couple was baby-sitting their goddaughters, ages 6 and 9, when they were killed, officials said. They are the daughters of Brookshire Mayor Joseph Vaughn.

Investigators said the girls woke up to use the restroom and found Jackson's body. The girls called their mother, who called police.

Brookshire police Chief Joe Prejean said he has identified a person of interest who may know something about the slayings. Prejean said that person, whose name was not released, was questioned for several hours and released without charges being filed.

"We have an obligation to the victims," Prejean said. "We have an obligation to do things the right way. It's always been my belief that we move slow. It's not going to do us any good to put anyone in jail on this thing and they're released because of something we failed to do."

Police said they questioned two teens on Thursday about the killings. They were later released.

Prejean said he believes robbery was the motive for the killings. Money was taken from the home, he said.

Jackson was known to carry a large amount of cash and share it with family and friends.

The Texas Rangers are participating in the investigation.

Anyone with information is asked to call Brookshire police at 281-375-5000.