(CNN) -- Despite claims to the contrary, the Syrian government is almost certainly responsible for a blackout Thursday that shut down virtually all Internet service in the country, according to a leading Web security firm. "The Syrian Minister of Information is being reported as saying that the government did not disable the Internet, but instead the outage was caused by a cable being cut," writes Matthew Prince, CEO of CloudFlare. "From our investigation, that appears unlikely to be the case." Fighting again between rebels and forces loyal to President Bashar al-Assad disrupted much of Damascus on Friday, and there was no Internet service throughout much of Syria for a second straight day. The airport was closed to flights, and fighting killed another 31 people across the country on Friday, according to an opposition group that counts casualties.
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Security CEO: Syrian government almost certainly shut down the Web
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Analysts say essentially all Internet connections to Syria have been killed
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Syrian rebels have used Web to share images of conflict with Assad regime
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Google letting Syrians tweet by using voice-only phone calls
But Prince said only four @placeholder cables connect Syria to the outside world.