Hostage envoy Roger Carstens traveled to Syria Friday, making the first known U.S. in-person contact with the caretaker government, and seeking help in finding missing American Austin Tice.

We should ask the militants who toppled Bashar al-Assad in Syria what became of missing U.S. reporter Austin Tice and why

We hold Bashar al-Assad and his criminal regime accountable for the consequences of Austin’s disappearance and the pain inflicted on his mother — pain, tears and separation," a spokesman told NBC News.

The mother of Austin Tice, who was taken captive in Syria in 2012, voiced hope that upheaval in the country will lead to freedom for her son.

Nongovernmental workers and journalists have scoured prisons for clues about his fate in the absence of an official American presence in the country.

There are no credible hints of his whereabouts, but also no clear evidence that he is dead, a U.S. official said.

The recent fall of the Assad regime has infused new hope in the search for Austin Tice, an American detained in Syria for a decade, as prisoners in jails across the country are released, Gustaf Kiland

Journalist Austin Tice was taken hostage in Syria twelve years ago. Now there's finally reason to believe he may return. The U.S. government must act.

The fall of the Assad regime in Syria has led to the freeing of tens of thousands of prisoners from the country’s brutal and byzantine prison system. Desperate family members continue to search for many more people who went missing since repression of an anti-government uprising triggered a horrific civil war in 2011.

Russian President Vladimir Putin said he would enquire about the whereabouts of Austin Tice, the American journalist missing in Syria, while responding to a question from an NBC correspondent at his lengthy end-of-year press conference.

More than any moment since he was taken from us, we have a reason to believe that Austin Tice may return from Syria.