The sister of a Georgia 911 dispatcher who has been missing for 12 days said she believes her sister's estranged husband is involved in the disappearance.

Christina Hill told FOX News she had a gut feeling something bad happened to her sister, 41-year-old Theresa Parker.

Theresa was in the midst of a divorce from her husband, Sam Parker, when she disappeared over a week ago.

"I can honestly say that I do believe he's involved. That’s what I feel, that’s what I know in my heart," Hill said.

“I know of an incident last year where she was really scared, she was really afraid. And she looked me in the eyes and told me that she was afraid that she was going to die,” she added.

Police say they have not classified Parker, a sergeant with the LaFayette, Ga., police department, as a suspect.

However, FOX News learned late Saturday that the Georgia Bureau of Investigation obtained a search warrant for Parker's home based upon information gathered over the past week. There was no word if the search had been carried out yet.

Parker's home has been search twice before under his consent and with him present.

Theresa's other sister, Hilda Wilson, told FOX News she hasn't heard a word from her sister's husband since the search began, but refused to comment on whether she suspected him.

"We're still hopeful that we're going to be able to being her home safe and sound. If not we just want to bring her home," Wilson said.

Investigators are continuing a widespread search for Theresa Saturday that includes 168 volunteers, a dive team and five dog teams. The search will continue until nightfall, and begin again on Sunday morning, rain or shine.

The patrol car of Sam Parker was routinely turned over to the Walker County Sheriff's Department, then to the Georgia Bureau of Investigations, to be examined, FOXNews.com confirmed.

"The car was brought in yesterday and the chief of police turned that vehicle over to us to examine, the GBI to examine, to look at more for investigative purposes, whether to rule in or rule out the fact that that car could've been used. We're not saying that car was used," Walker County Sheriff Steve said Friday.

The car was being released back to the Lafayette police on Friday.

Police say the more time that passes since Theresa has been seen, the less likely she will be found alive.

"Certainly you have to look at that and believe that at this stage of the investigation," Wilson said. "At some point, obviously, we will maybe change the focus of this investigation probably from a missing person to possibly a death investigation of some sort if the evidence leads us this way."

There is no evidence pointing to another man in Parker's life, Wilson said, and there has been no use of her credit or debit cards since she disappeared. Her husband indicated her purse and an overnight bag were missing from the house she was living in, but besides that, the residence was immaculate.

Records show at least three domestic violence reports between Parker and her husband since 2002, according to local news reports.

Sam Parker had moved out of the home he and his wife once shared, and Theresa was in the midst of moving to a neighboring town when she disappeared. Sam has not been named a suspect and has been interviewed several times by investigators.

"He's been cooperative so far, so far has answered our questions," Wilson told FOXNews.com earlier this week. "At this point I would not classify him as a suspect, he's certainly been cooperative but on the flip side, we have not eliminated anyone as a suspect, either."

Sam Parker was fishing with LaFayette attorney Bill Slack the same time on Wednesday when Theresa's family last saw her, reported The Walker County Messenger. Slack had represented Theresa and others in her family in the past. He said Sam was acting completely normal, and seemed relieved that the divorce was going through.

Click here to read the Walker County Messenger

The death of both of Sam's parents within the last year left him with no financial worries. The terms of divorce had been established, the property had been divided and the papers were reportedly ready to be filed any day, Slack told the newspaper.

"It was done," Slack said. "There was no more fussing or anything. It was all done. That part of his life was over."

Slack said he knew the couple had their problems, but didn't suspect violence was ever an issue. He also said Sam has willingly complied with the investigation into his wife's disappearance, and that his house, car, father's house and wife's car have all been searched. He even turned over his bank and phone records and had his clothes and body tested for fluids.

"I'd like to think they've exhausted any probability that Sam was involved because there seems to be nothing to point to him physically, motive-wise, opportunity. Nothing," Slack told the newspaper. "If Sam had anything to do with her disappearance it would be an absolute shock to me."

He added: "They've done everything you can think of and there is nothing to tie him to her [disappearance]. He doesn't know where she is and he certainly didn't harm her. He had no reason to harm her."

Relatives of Theresa Parker's contacted the Walker County sheriff's office on Saturday. She was last heard from about 10 p.m. Wednesday when she talked on the phone with her sister, Wilson said. It was Parker's habit to talk to her mother or other relatives at least once a day.

"Obviously this is totally uncharacteristic for her. ... She's always been a very punctual type person who is very dedicated to her job, her family," Wilson told FOXNews.com.

No one at the 911 dispatch center noticed her absence, Wilson said, because she was scheduled to be off work. But she failed to show up Monday for her 7 p.m. shift.

"We knew then, we're just very, very concerned at this point because this is just not typical for her," Wilson said.

The case was turned over to the Georgia Bureau of Investigation because of the close ties between Parker and the local authorities, Wilson said. She has been a 911 operator for about 15 years, and worked as a police emergency dispatcher before that.

Wilson, who knows her personally, described her as a "very knowledgeable, very thorough employee, a very likeable person."