The Iraqi branch of al-Qaeda carried out two recent bombings in Damascus and was likely behind suicide bombings that killed at least 28 people in the Syrian city of Aleppo, according to a media report.
Citing unnamed US officials, McClatchy Newspapers said the incidents appeared to verify Syrian President Bashar Assad's charges of al-Qaeda involvement in the uprising against his rule.
The Syrian opposition has claimed that the Assad regime had staged the bombings to discredit the pro-democracy movement, the report said.
The first Damascus attack occurred on December 23, when suicide bombers detonated cars packed with explosives outside intelligence agency compounds, killing at least 44 people.
On January 6, at least 26 people were killed and dozens injured in a bombing against a second intelligence agency compound.
The al-Qaeda presence in Syria also raises the possibility that Islamic extremists will try to hijack the uprising, McClatchy Newspapers said.
US intelligence reports indicate that the bombings came on the orders of Ayman al-Zawahiri, the Egyptian who assumed leadership of al-Qaeda after the last year's death of Osama bin Laden, the newspaper chain noted.
US officials said that al-Qaeda in Iraq (AQI) began pushing to become involved in Syria as Assad's security forces and gangs of loyalists launched a crackdown on opposition demonstrations, igniting large-scale bloodshed, the report said.
Zawahiri finally authorised AQI to begin operations in Syria in what's believed to be the first time that the branch has operated outside of Iraq, McClatchy Newspapers pointed out.