(CNN) -- Authorities in North Dakota reached out Monday for the public's help in finding the body of a missing Montana teacher they believe is dead and buried in their area, offering a plea on the same day two men were in court in connection with the woman's disappearance.
"We feel it prudent to request help from landowners," Williston, North Dakota, Police Chief Jim Lokken told reporters. "We have reason to believe that she may be buried in an area that contains trees that may be matured, dying or rotting."
The two men being detained were in a North Dakota court Monday and are being held "on no-bond warrants out of the state of Montana for aggravated kidnapping," said Williams County, North Dakota, Sheriff Scott Busching.
Their apparent victim is Sherry Arnold, a 43-year-old mother who was last seen nine days ago while out on a morning jog in her small town of Sidney, Montana. Police found one of her running shoes along her route.
The Sidney Public Schools, where Arnold was a math teacher at the town's high school, announced Friday on its website that she was dead. But two days later, the FBI issued a statement in which they said that, while they believe Arnold is dead, her body still has not been found.
"This is a crime of the century for us," Mayor Bret Smelser told HLN's Jane Velez-Mitchell on Monday night. "We're still grieving, we're still somewhat frustrated. At this point in time, we want to get closure -- for the family especially, and the community."
Authorities have offered little information about the two men charged in her disappearance, including why they were in Sidney, how they might have come across Arnold, and what they allegedly did to her.
Busching, the county sheriff, said that the 47-year-old Lester Vann Waters was arrested in Williston, about 50 miles northeast of where Arnold went missing. The other man -- Michael Keith Spell, 22 -- was taken into custody in Rapid City, South Dakota, and then transported to North Dakota. Their arrests were announced last Friday.
Waters has been arrested for numerous offenses over the years including illegal weapon possession, fraud, theft and various drug-related charges, according to a criminal background check.
Both he and Spell are from Parachute, Colorado, and are now in the Williams County jail, Williams County Deputy Cindy Gergen told CNN.
The pair are being held at the request of Montana authorities and could soon be extradited to that state, according to the sheriff. "At this particular time," neither man is in a position to help locate Arnold's body, Busching said.
Arnold's disappearance prompted hundreds to turn out last week to look for her, until the FBI announced Wednesday that it was scaling back its search efforts.
Frank DiFonzo, the police chief of the eastern Montana town of about 5,200 people situated 100 miles south of the Canadian border, on Monday praised the response from the public and other law enforcement agencies.
"It's just been amazing, how many people have stepped up and offered their assistance and sent out condolences," DiFonzo said from Williston, where he attended the press conference with Buschin and Lokken. "It's all over the country. We appreciate that."
Lokken, the Williston police chief, stressed Monday that authorities aren't asking volunteers generally to launch another search "because of the cold and public safety."
"We don't want the public out there, running around the countryside," Lokken said of the proposed search area in northwest North Dakota. "If they see anything that's disturbed, we'd like them to call."
Sidney's mayor said that, once Arnold's body is found, it is time to have a "serious discussion as to where we go from there." Specifically, he mentioned that the community may want to take a different approach to the influx of outsiders coming to the area for oil industry-related jobs.
"We're not going to point the finger at anybody, (but we could consider) asking, maybe you can run a criminal background check," Smelser said. "I think that's something that we need to discuss."
The town's police chief, though, said it could be unfair to jump to too many conclusions about those who haven't been long-time residents, based on Arnold's apparent kidnapping. He urged the public to maintain an open mind and perspective about how rare this incident was.
"What we have here are a couple of individuals that somehow decided to come through our area and, we believe, commit a crime," said DiFonzo. "I just don't think it's fair to criticize one group of people and eliminate anybody else."
CNN's Antoinette Campbell and Greg Morrison contributed to this report.