Updated

The mother of an American journalist who vanished in Syria in 2012 is urging everyone to encourage and remind President Obama of his “obligation” to bring her son home.

Austin Tice, a Marine and Georgetown Law student from Houston, disappeared in August 2012. A video released a month later showed the journalist blindfolded and held by armed men. He has not been heard from since.

“It helps tremendously when people pray for Austin, pray for his release, pray for us to continue to have the strength to work and wait for him to come home,” his mother Debra told Fox News' “Happening Now” on Thursday.

She also urged Americans to “continue to encourage and remind our president of his obligation to bring Austin home.”

Debra Tice said she never expected to hear the news of her son’s disappearance and that the ordeal would last 1,543 days and counting. Relatives have said it was unlikely Syrian rebels, the government or the Islamic State terror group were holding him hostage.

The Newseum in Washington, D.C., on Wednesday unveiled a special 24-foot-long banner displaying a large photo of Tice, saying that the banner would remain on display until he comes home.

The 43-second video released of Tice shows him blindfolded and with his hands bound, being led up a rocky hillside by a group of heavily armed men chanting in Arabic, "God is great."

"It’s mysterious and very inconclusive," Tice's father, Marc, had said of the film. "We've had a lot of people look at it and no one has been able to say definitively who the people are and where they're from."