- Sherry Arnold, 43, went for a run on Saturday and hasn't been seen since
- Authorities found a lone shoe on her route but haven't disclosed anything else
- The FBI says it has scaled back its search, even as it pleads for more information
- Arnold's husband says he trusts the FBI, adding simply, "We want her back"
With time ticking by and an apparent dearth of clues, an eastern Montana family clung Thursday to hopes of finding a 43-year-old schoolteacher, last seen five days earlier out on a morning jog through her small town.
An FBI official noted that investigators have received "dozens and dozens" of calls about Sherry Arnold, agency spokeswoman Deborah Bertram said Thursday by e-mail. But the woman remains at large, and there are no named suspects in her disappearance.
"Our thoughts are focused on her, we want her to return, we want to get her back," her husband, Gary Arnold, told HLN's Jane Velez-Mitchell on Thursday. "That's what keeps hope alive."
Sherry Arnold went running around 6:30 a.m. Saturday, but never returned home, the FBI said.
Other than one of her running shoes that was found along her route, authorities have not indicated there's been any sign of Arnold.
This is despite an extensive search effort launched by authorities and aided by throngs of people around the area. Sidney police Chief Frank DiFonzo said earlier this week that teams had been using dogs and aircraft and have gotten help from National Guard members as well as volunteers.
Christine Mullen, 26, a CNN iReport contributor, said earlier this week that she went to the site of one of the searches, where thousands turned up to help. Some set out on horses, others on ATVs and more on foot covering "a lot of pasture, dirt roads and farmland."
Arnold's disappearance has hit the small community hard, including at Sidney High School, where she is a math teacher. Situated near North Dakota and about 100 miles south of the Canadian border, Sidney has a population of just under 5,200 people, according to the U.S. Census Bureau.
"Everybody is involved," said Mullen, adding she doesn't know Arnold but still feels the impact. "We're such a small community, and crime is absolutely unheard of," Mullen said. "We don't lock our car doors. (We're) completely shocked."
But this type of extensive effort was called off Wednesday, when the FBI announced that "law enforcement officials determined the prudent course of action is to scale back the ground search."
The focus, instead, will shift toward "other investigative efforts," though the FBI did not specify in its statement what those would be.
"I think the FBI is on top of it, as much as they can be," said Gary Arnold, adding that he believed his wife's running route has been "very, very thoroughly searched."
"They're going to do the right thing and ask the right questions from the right people. We just need to get that one tip."
On Thursday, the FBI put out a poster of Arnold and added her to its "kidnapping and missing persons" website. It noted that she was wearing running clothes, mittens, earbuds and a grayish-blue iPod at the time of her disappearance.
"We are hopeful this will generate more tips in the case," Bertram said. "Our goal is to keep her information and picture out in the public."
Frigid temperatures have heightened concerns. The low temperature Thursday night in Sidney was expected to dip to 15 degrees Fahrenheit, with daytime highs over the next two days forecast to be in the 30s, according to the National Weather Service.
Gary Arnold said his wife's disappearance has been "very difficult" on the couple's children, though he said they are staying optimistic.
"Their mother has raised them well," he said. "They are troupers, they are hanging in there, and they are not giving up hope either."