A group calling itself the Syrian Electronic Army (SEA) claims to have hacked Skype's social medial platforms. The group posted a warning on Skype's sites not to use Microsoft's e-mail service because "they are monitoring your accounts and selling data to the governments." Microsoft owns Skype.
The hacked post, which has been removed, was placed on Skype's blog and Twitter account, according to BBC reports Thursday.
In response, Skype stated that "no user information was compromised" during the hacking.
Previously SEA, which supports President Bashar Assad's regime, has claimed responsibility for several cyber attacks, such as one on the New York Times website in August.
The group also apparently hacked the US Marines' website in September, redirecting site visitors to a screen calling US President Barack Obama "a traitor who wants to put your lives in danger to rescue Al Qaeda insurgents."
In May, the satirical news site The Onion had its website breached by SEA, who posted tweets such as "UN retracts report of Syrian chemical weapon use: 'Lab tests confirm it is Jihadi body odor,'" and "UN's Ban Ki Moon condemns Syria for being struck by Israel: 'It was in the way of Jewish missiles.'"
The recent hacked warning about Microsoft surveillance comes amid the leaking of secret National Security Agency (NSA) documents by Edward Snowden, which revealed massive and systemic spying conducted by the US even on allies.
Whistleblower Snowden recently said his coworkers at NSA were "astonished to learn we are collecting more in the United States on Americans than we are on Russians in Russia."
The leaked documents revealed that intelligence agencies had access to the servers of major technology companies including Microsoft, Yahoo, Google, Facebook, Paltalk, AOL, Skype, YouTube and Apple. All the companies have denied involvement.
Following the revelations, an alliance called Reform Government Surveillance group has been formed by Microsoft together with Google and others, calling for "wide-scale changes" to US surveillance.
In response to rising threats of hacking, especially from Syria, China and Iran, many countries have looked to tighten internet security. For that purpose, the Israel Electric Company recently opened a "cyber gym" to train defense against cyber attacks.