While protests sweep the streets of Venezuela, the nation's government is quietly tightening its grip on the Internet.
Last week, the government blocked its citizens from uploading and viewing pictures on Twitter. Now officials are warning that social networks are being used by "cybercriminals" to spread misinformation and support what they call a "coup."
See also: Protests Persist in Venezuela: 24 Photos From the Conflict
Citizens of the Western state of Tachira reported on Thursday that the Internet was down statewide, and other activists warned that the government is slowing down connections at night, when police forces attack protesters.
Renesys, an Internet monitoring and research firm, couldn't officially confirm the outage. But Doug Madory, one of the firm's researchers, told Mashable it had seen drops in bandwidth and increases in latency that might be caused by throttling, although he couldn't be certain of the cause.
All these disruptions seem to be part of a plan to keep the population in the dark about the protests. "There is no independent media, so the national TV doesn't show that there are demonstrations around the country," Marianne Diaz Hernandez, a Venezuelan activists who founded AccesoLibre, an Internet freedom advocacy group, told Mashable.
"There's part of the country that doesn't have any idea what's going on, and another that goes online and looks for information on social networks."
The government has the legal power to block websites it deems as a threat to national security, or sites that show independent or opposing views, according to a report by the watchdog group Freedom House. This censorship powers have been seldom used, but the government seems more willing to censor websites around big political events such as the April 2013 elections, held after the death of former president Hugo Chavez.
Venezuelan government agencies didn't respond to Mashable's requests for comment.
Diaz Hernandez is collecting reports of blocked websites through Herdict, a crowd-sourcing tool that allows users to flag websites that they cannot access. Diaz Hernandez warned that the results are not comprehensive yet, but several Venezuelan Internet users reported the blocking of Twitter, Facebook and the news site La Patilla. A graphic of the partial results of her survey can be seen here.
The government's censorship power is helped by the near-monopoly of CANTV, the state-owned Internet provider, which controls more than half broadband connections in Venezuela, according to Freedom House. By controlling the main Internet provider, the government can simply order CANTV to shut down all Internet service — as it did for 30 minutes during the April 2013 elections — or strategically block certain websites.
"The government doesn't necessarily have a kill switch," Andres Azpurua, the director of Venezuela Inteligente, a
freedom of information organization that promotes transparency, told Mashable. "But it doesn't need it."
Activists like Diaz Hernandez and Azpurua are trying to fight back, promoting the use of Virtual Private Networks (VPN) or Tor to circumvent censorship. Commercial VPN companies such as TunnelBear and Hotspot Shield have contributed by offering their software free of charge to Venezuelans.
Thanks to two laws that regulated online media, passed in 2010, the government can also request independent ISPs to block certain websites and impose high fines if they refuse.
Until recently, blocking wasn't the preferred weapon in the government's online arsenal. President Nicolas Maduro said last year that "if lies come through Twitter, we are going to strike back through Twitter."
That led to a group of paid government online commentators who spread official propaganda, harass critics on Twitter, and attempt to steer the online conversation. The government called this campaign the "Communication Guerrilla," when it launched in 2010.
Several officials have recently warned of opposition "disinformation" being spread on Twitter. Delcy Rodriguez, the country's Communications and Information Minister, tweeted that social networks are used by "violent coup leaders" to "create anguish within the population in a large scale psychological operation."
The director of CONATEL, Venezuela's National Telecommunications Commission, echoed Rodriguez in a tweet, writing: "Social networks are being invaded by cybercriminals who hijack accounts and manipulate information."
Those are the tactics activists and international experts attribute to the Maduro regime.
"Manipulation of online content by the ruling party and its supporters has compromised the atmosphere of free online debate," wrote Freedom House. "Such careful management of content has included steering conversations along pro-government lines, hacking, discrediting opposition voices via Twitter impersonations, and encouraging self-censorship."

A group of pro-government hackers, called N33, has hijacked a number of journalists' Twitter accounts. Much like the Syrian Electronic Army, N33 is said to be government-sponsored, but the hackers have denied being paid by the regime.
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