"If this turns out to be true, this is terrific news," Toner told reporters. "The hikers' release is long overdue. And I would just stress that we hope that it's all three hikers."
After more than nine months of desperate pleading, including direct appeals to Iranian president Mahmoud Ahmadinejad, the hikers' mothers were allowed to see the detained Americans briefly in Iran in May this year. The group was detained under accusations of espionage.
In May, Shourd's mother told "Good Morning America" she was concerned about her daughter because Swiss officials had told her Shourd was depressed. At the same time, the Associated Press reported Shourd was suffering from a serious gynecological condition.
After the initial reunion with their mothers in May, the three hikers spoke to reporters and described their captivity.
Shourd, who spent a majority of her captivity alone, said the food was "good" and, "we have medical care which is appreciated."
Bauer, 28, said the group had a "decent relationship" with the guards and that "it's been civil."
Fattal, 28, said the officials eventually allowed the American to have books while in confinement.
"Once we started getting books that really helped the prison experience a lot," he said.
Before their brief reunion with their children, the mothers made a public plea toIranian officials to set politics aside and release their children.
"The two countries are at odds with each other and we don't want this mixed in with that," Cindy Hickey told "Good Morning America" in early May.
Those tensions have been heightened by the U.S. effort to impose new sanctions on Iran in an effort to convince Iran to abandon its nuclear ambitions.
In an earlier interview with ABC News' George Stephanopoulos Iranian president Mahmoud Ahmadinejad said it was up to a judge to decide whether the hikers were telling the truth when they claimed that they simply got lost.
"They have to provide proof and evidence to the judge in Iran that shows that they lost their way or made a mistake," Ahmadinejad said then. "When the time comes, they will have a lawyer."
The Americans, all University of California-Berkeley graduates, entered northern Iraq with visas from Turkey on July 28 and planned to spend five days in the area, according to a Web site dedicated to the hikers' release.
"There's no doubt in my mind that if they crossed the border by accident, it was by accident," Bauer's mother, Cindy Hickey said.
In the early May interview, Ahmadinejad said he would make a recommendation to the judge to "render maximum cooperation" in regards to the case, but said he had no influence over the judge. The mothers said they saw more when they watched the interview.
"We saw compassion in his face during that interview," Laura Fattal said afterwards. "I think President Ahmadinejad -- his face changed when you spoke about the children."
ABC News' Jim Sciutto, Jason Stine and The Associated Press contributed to this report.