Two days later the agency’s tech news Twitter feed was taken over and pro-Syrian government messages posted.
It is unclear who is behind the hack.
Reporting on the breach, Reuters said that cyberwar between the pro and anti-government factions in Syria had intensified with Saudi Arabia emerging as a staunch opponent of Assad.
It offered little more detail on how its system had been breached.
“Reuters.com was a target of a hack on Tuesday. Our blogging platform was compromised and a fabricated blog post saying Saudi Arabia’s Foreign Minister Prince Saud al-Faisal had died was illegally posted on a Reuters journalist’s blog on Reuters.com,” said a spokesperson.
“Reuters did not report the false story and the post was immediately deleted. We are working to address the problem,” the spokesperson added.
Reuters uses the WordPress platform for blogging and, after the first attack Mark Jaquith, a member of the WordPress security team, told the Wall Street Journal that it was using an old version of the software, known to have security issues.
The agency has not been the only victim of spoof attacks related to the conflict in Syria.
A group calling itself the “Syrian Electronic Army” claimed responsibility for defacing a Harvard University website to post a picture of President Bashar al-Assad in military uniform last year.
Last week, a Twitter account purporting to be that of a senior Russian official said that Mr Assad had been killed in Damascus. It was later confirmed to be false.