At least three members of Dutch biker gang have joined up with Kurdish fighters in Iraq, according to Agence France Presse. The trio belong to a group known as "No Surrender," a gang with chapters across the country.

Their leader, Otto Klaas, confirmed that three had traveled recently to join the front-lines of the pesh merga in the battle against the Islamic State. A Kurdish-Dutch Twitter account posted a picture of one of the supposed Dutch bikers, sporting a Kurdish keffiyeh and clutching an automatic rifle alongside a Kurdish fighter in what appears to be a bunker.

The three members of the biker gang who went to Iraq are all believed to be ex-military or Dutch special forces. It's unclear what motivated them other than sympathy for the Kurds, whose various militias in Iraq and Syria have been locked in battle with Islamic State forces for months now. There's a significant diaspora of ethnic Kurds in Holland, though it doesn't seem the bikers are Kurds themselves.

Biker gangs in Europe are not known for their solidarity with people from the Middle East; rather, they tend to be outfits dominated by right-wing nationalists. One prime example is Russia's Night Wolves, a biker gang publicly embraced by President Vladimir Putin. Amid the turmoil in Ukraine, Night Wolves deployed to Crimea to help aid Russia's annexation by Moscow and paraded through parts of eastern Ukraine in the grip pro-Russian separatists.

In Syria and Iraq, much of the attention in recent months has fallen on foreign fighters journeying there to join up with the Islamic State, an extremist jihadist organization that has mushroomed in power and influence this year. On Thursday, a new video emerged of European fighters in the Islamic State, uttering stark threats against the West. "We will chop off the heads of the Americans, chop off the heads of the French, chop off the heads of whoever you may bring," warned a British jihadist on camera.

But there are cases, albeit far fewer, of foreigners traveling to the region to join factions fighting against the Islamic State or for the Syrian regime of Bashar al-Assad. There was the bizarre video in March of two supposed L.A.-area gangsters firing weapons from a blasted building while invoking Assad's name and their other "homies" in southern California.

And earlier this month, reports emerged that three Americans had joined Kurdish fighters in Syria. One person identified by the People's Protection Units, a Syrian Kurdish militia known by its acronym YPG, is former U.S. soldier Jordan Matson, from Wisconsin. He also posted a picture of himself in Kurdish attire, clutching a gun.

Unlike those who join the Islamic State, the Dutch bikers among the Iraqi Kurdish pesh merga likely won't face prosecution when they return home. "Joining a foreign armed force was previously punishable, now it's no longer forbidden," a Dutch legal official told the AFP. "You just can't join a fight against the Netherlands."

But it is a crime to join a terrorist organization. The YPG is affiliated with the PKK, a Kurdish separatist organization based in Turkey that, while instrumental in the fight against the Islamic State, is considered a terror group by Ankara, Washington and much of the international community. It's just another curious wrinkle amid the horrible mess of the conflicts raging in Iraq and Syria.