(CNN) -- U.S. journalist Austin Tice, who went missing while working in Syria two weeks ago, has been captured and is being held in Syrian government custody, The Washington Post reported Thursday, citing a senior diplomat and others familiar with the matter.
The Post is one of several news outlets for which Tice, 31, filed stories since he began reporting from Syria in May. He also reported for McClatchy Newspapers and Al-Jazeera English.
Tice's family immediately called for his release, saying in a statement, "Austin is our precious son, and we beseech the Syrian government to treat him well and return him safely to us as soon as possible."
The executive editor of The Post, Marcus Brauchli, also urged authorities to release Tice, as did Anders Gyllenhaal, McClatchy's vice president for news.
"We welcome the news that Austin Tice is likely being held by the Syrian government, although this has still not been confirmed by government authorities," Gyllenhaal said in a statement. "If this is indeed the case, it means we move to a new stage of waiting for his release.
"There's no basis for detaining a journalist. Austin is a respected and very dedicated reporter and we would expect his immediate release."
Tice's last public post was August 11 on Twitter, where he said he spent the day with members of the rebel Free Syrian Army at a pool party with music.
The U.S. State Department has been working through the Czech Embassy in Damascus to learn details of Tice's whereabouts.
The Post and the Committee to Protect Journalists, an advocacy group, both reported it was the Czech ambassador to Syria who first revealed the news about Tice on Thursday.
Reporters Without Borders, another advocacy group, says Syria is one of the most dangerous places for journalists. Ten have been killed since the start of the conflict early last year, it says.