Web traffic in Syria has returned after an approximately 20-hour period during which the entire country appeared to be cut off from the Internet, according to Web analysis firms.

Firms that track Web traffic, including Renesys and Akamai, showed a major spike Wednesday morning after essentially no activity from Tuesday afternoon to Wednesday morning.

According to a report from the BBC, Syrian state-run media said the outage was due to a “fault” in optical fiber cables that connect the country to the World Wide Web.

The Associated Press reported that traffic has been restored, and that there had been no accusations from within the country that the blackout was an act of political sabotage.

But, as The Washington Post’s Max Fisher noted, there is reason to be skeptical of claims that the blackout was linked to a cable fault.

Syria has four different sets of cables that connect it to the Web, Fisher wrote, and a simultaneous disruptions to all resulting in the kind of blackout Web monitors have recorded seems implausible.

Several open Web advocates, including the Electronic Frontier Foundation and the Center for Democracy and Technology, wrote that they believe the blackout was a deliberate attempt to silence government criticism.

The Internet, EFF International Director Danny O’Brien noted, has been a valuable tool for Syrian activists.

“While heavily censored, monitored, and compromised, the Internet has served as an important window connecting the world at large to Syria, and one way that international observers could connect with individuals on the ground in that country,” O’Brien wrote in a blog post Tuesday.

This is the second time that the Syrian Internet has gone dark in the past year — in November 2012, the country’s Web traffic went dark for over two days.

Following that blackout, the Center for Democracy and Technology called on the United Nations to condemn countries that purposefully shut down Internet access for their citizens, saying that such blackouts are an “indefensible violation of human rights.”

Related stories:

WorldViews: How did Syria cut off the entire country from the Internet?

WorldViews: A stunning chart shows Syria’s Internet blackout

State media say Internet service in Syria has been restored after countrywide outage

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