When it comes to covering Syria, the fog of war is especially thick.

For 17 months, President Bashar al-Assad's regime has severely restricted press access in the country as his soldiers first brutally cracked down on peaceful protests and now battle opposition forces in a war that has claimed more than 19,000 lives.

Western journalists have occasionally snuck into Syria, but on a daily basis primarily rely on information provided by opposition activists, residents, state-controlled media, rebel commanders, social media and anti-regime groups operating outside the country. Meanwhile, each warring side simultaneously fights a public relations war in the media.

Several Beiruit-based correspondents told The Huffington Post that their outlets have gotten better at vetting information throughout the lengthy conflict and have built a large network of reliable sources in the process. Still, news reports on the latest explosion, firefight or alleged massacre routinely acknowledge that key details cannot be independently verified and correspondents say that this is not the ideal way to cover a war.

"It's the most frustrating situation I've ever been in and potentially the most challenging," said Arwa Damon, a Beirut-based correspondent for CNN. "Now you're trying to newsgather via remote."

Damon last reported inside Syria in February, an ordeal chronicled in CNN's documentary "72 Hours Under Fire." After three days, she left the war-ravaged city of Homs, north of Damascus, alongside veteran war correspondent Marie Colvin, who later reversed course and was killed in the city. Colvin is one of 16 journalists killed so far, according to information provided by the Committee to Protect Journalists.