Forty-eight Iranian pilgrims were kidnapped from a bus in the Syrian capital on Saturday, their embassy's consular chief in Damascus told Iran's state television.
"Armed terrorist groups kidnapped 48 Iranian pilgrims on their way to the airport," Majid Kamjou told the IRIB network, which gave the report on its website.
"There are no reports about the fate of the pilgrims. The embassy and Syrian officials are trying to trace the kidnappers," he said.
Hundreds of thousands of Iranians travel each year to Syria to visit a Shiite pilgrimage site, the Shrine of Zaynab, in Damascus.
Tehran is the staunchest ally of Syrian President Bashar al-Assad, whose forces are locked in a bloody conflict in Damascus and other cities against rebels his regime describes as "terrorists".
Several dozen Iranian pilgrims and engineers were abducted in December and January, with most being released months later.
Many of the rebels come from Syria's Sunni majority, which is hostile to the support Shiite Iran has shown to the regime of Assad, whose family is Alawite, a Shiite offshoot.