A group of Islamic militants have launched an organisation called "Taliban of Syria" and issued decapitation warnings against anyone who cooperates with President Bashar al-Assad's regime.
"We will decapitate anyone who interacts with the Syrian government, even if he/she is a Muslim," the group said in a statement.
It has also vowed to carry out targeted attacks in Syria against other religions and sects.
The two-year-long uprising in Syria has spawned several militant groups. Al-Qaida, the Lebanon-based Hezbollah and the Taliban are all present in the country.
In a recent interview with CNN, King Abdullah II of Jordan warned of the emergence of the Taliban in Syria.
"Well, al-Qaida is established in Syria. They've been there for about a year. They are getting certain supplies of material, weapons and financing, unfortunately, from certain sectors," the King said. "When we look at Jordanian troops deploying to Afghanistan, we've got to really think, because I think the new Taliban that we're going to have to deal with is actually going to be in Syria."
Earlier reports speculated that Afghan- and Pakistan-based Taliban militants have been heading to Lebanon and Turkey.
According to Iran-based reports, which usually support Assad, dozens of Taliban fighters have already joined the ranks of the Free Syrian Army (FSA), the main armed opposition group in Syria.
The Taliban's emergence in Syria comes at a time when the US has doubled its non-lethal military aid to the Syrian rebels.
US Secretary of State John Kerry told a Friends of Syria meeting in Istanbul that the rebels would receive $123m (£81m). Kerry said the situation in Syria is "horrific and horrible". However, he said that the Obama administration believes a political solution is still possible in the strife-torn country.