Russia is recruiting fighters in Syria to fight in Ukraine, The Wall Street Journal reported, a move that can bring Iran-backed fighters into the war in Europe.

There are a myriad of groups fighting in Syria, including local persons fighting for Russia’s ally Iran and the Bashar al-Assad’s forces, the Lebanese Hezbollah, Afghan and Iraqi fighters recruited and paid by Iran, and Jihadist groups opposed to Iran and Russia.

The report, quoting US officials, did not provide details as to whether Syrian citizens are being recruited or foreign fighters. But if Russia has indeed decided it needs foreign fighters in Ukraine it might not hesitate to send non-Syrians recruited by Iran to Europe.

Iran entered the Syrian conflict from its early days in 2011 and in more than a decade has sent tens of thousands of Afghans, Iraqis and even Pakistanis to fight in Syria. In addition, the Iran-backed Hezbollah in neighboring Lebanon has been fighting in Syria alongside Iran and Russia for almost a decade.

Fighters in Syria not only have long experience in battle but many have fought in urban battles such as the capture of Aleppo from Assad’s opponents in 2016.

Other reports say that Moscow is also sending mercenaries from Russia to fight in Ukraine.

Many foreigners have also volunteered to fight on the Ukrainian side.