From the Washington Post:

Two Los Angeles gang members appear to have joined the flow of foreigners flocking to fight in Syria – in this instance, on the side of President Bashar al-Assad. In a video posted online, the two men boast that they are on the front lines and fire their guns in the direction of what they call "the enemigos."
One of the men identifies himself as Creeper from the Sur-13 or Surenos, a loose affiliation of southern California gangs linked to the Mexican mafia. He rolls up his sleeves to show his gang tattoos and greets fellow gang members Capone-E and Crazy Loco.

The other says he is called Wino, and belongs to a gang called Westside Armenian Power. Members of the Armenian Christian minority in Syria are known to be staunch supporters of Assad.

The two men don't reveal much about what they are doing or why they are fighting for Assad.
"It's Syria, homie, we're in Syria, homie. ... Frontline, homie, frontline, homie," says Wino.
"In Middle East, homie, in Syria, still gangbanging," says Creeper, in comments typical of the 2 1/2-minute video.

Warning: the video, posted here, contains strong language. This version is provided by the Middle East Media Research Institute, and contains subtitles.
It was impossible to independently verify the authenticity of the video or determine where or when it was filmed. But the desolate scene in which the two men are firing from a bombed building looks like Syria.

The Middle East Media Research Institute, a pro-Israel group that monitors media in the region, said it had identified Wino as Nerses Kilajyan, whose Facebook page features multiple photographs of the man who calls himself Wino, apparently in the northern Syrian city of Aleppo. In some, Wino is seen posing with fighters from the Shiite Hezbollah militia. In others, he is pictured with the man who calls himself Creeper. The dates on the photographs suggest the pair have been in Syria for about a year.

It was also unclear whether they are U.S. citizens. So far, there have been no reported instances in which Americans have volunteered to fight in Syria on behalf of Assad, though at least 50 U.S. citizens are believed to have traveled there to join the rebels, according to congressional testimony by Director of National Intelligence James Clapper last month. Thousands of Arabs, Europeans and Sunni Muslims of other nationalities who have flooded into Syria, most of them joining radical Islamist groups.

Thousands of Iraqi and Lebanese Shiite Muslims are meanwhile reported to be fighting on the side of Assad's government, as well as Iranians, some Russians and smaller numbers of Afghans, Pakistanis and other Arabs, making this a truly international war.