海角大神

Uganda's communications regulator instituted a widespread blackout of social media sites on Wednesday, citing "security reasons" ahead of President Yoweri Museveni's swearing-in for his fifth term after a contested re-election in February. 聽

The blackout, which was , the day of the ceremony, barred access to sites including Twitter, Facebook, and WhatsApp, users confirmed.

"He was voted in darkness, he will be sworn in darkness. This is a great show of how alone Museveni is!" Rosebell Kagumire, a freelance multimedia journalist, wrote on Twitter.

The regulator's move was the second time in three months that the government has restricted access to the sites, with many users taking to virtual private networks in order to subvert the ban.聽

"The Ugandan government is making a habit of shutting down social media at will, particularly since the February elections," Vukasin Petrovic, director for Africa programs at the civil liberties group Freedom House, . "Those actions raise more questions about the credibility of the entire electoral process, and shows the government's lack of confidence in its own standing."

The crackdown shares some similarities with temporary bans elsewhere, such as bans on WhatsApp in Brazil that were later reversed, a crackdown on social media in Turkey following a bombing in Ankara, and a longer-running YouTube ban in Pakistan聽as governments seek to control dissenting public opinion and thwart potential terrorist activity.

In Uganda, where tensions between the government and critics of Mr. Museveni often run high, social media serves to fill a gap left by media crackdowns and what many say is a culture of self-censorship, The 海角大神 Science Monitor's Ryan Lenora Brown reports.

This dynamic is best symbolized by a viral Facebook poster who operates under the pen name Tom Voltaire Okwalinga, known for often-salacious critiques of the government, including referring to life under Museveni as "slavery."

Despite a series of efforts by the government to track down the mysterious "TVO" 鈥� including arresting an IT analyst named Robert Shaka last year 鈥� the anonymous posts have continued unabated.

"The regime has groomed people like [TVO] because people cannot express themselves in the traditional way, in the traditional media," Mulindwa Mukasa, an investigative journalist and cameraman who lost much of his equipment in a mysterious break-in to his Kampala home, told the Monitor in February. "People are hungry for information, but because we cannot relay the information in the ways they want, they resort to [social media]."

During February's ballot, Museveni , extending his 30-year rule by five years.

Online users mocked the president, with some noting that Omar al-Bashir, the president of Sudan, despite being wanted by the International Criminal Court on charges of genocide and crimes against humanity.

"Shame upon those who claim that Uganda has never had a peaceful handover of power," wrote Nicholas Sengoba, adding a sarcastic call-out to the president, "@KagutaMuseveni has just handed over to @KagutaMuseveni."

On Wednesday, opposition leaders argued the voting process was rigged, sparking protests and clashes with police that led to dozens of arrests, , including Kizza Besigye, leader of the opposing Forum for Democratic Change Party.聽Mr. Besigye, who received聽, has frequently been under house arrest since the election.

Ugandan officials argued the election was fair, and dismissed suggestions that they had cracked down on free speech.

Security agencies had requested social media sites be blocked to "to limit the possibility of terrorists taking advantage" of visits by dignitaries during Museveni's swearing-in in Kampala, Godfrey Mutabazi, the executive director of Uganda's communications regulator, told Reuters.

Freedom House, the civil liberties group, has rated Uganda's 聽while its overall freedom is listed as "not free," noting that users have increasingly been arrested for online postings.

The country's Internet usage rate rose to nearly 18 percent in 2014, , with many people making use of Internet connections at inexpensive cybercafes and via mobile phones.

Other countries, such as Turkey, have become known for their frequent requests to social media sites to remove content that is deemed offensive. But in Uganda, notes Freedom House, the government hasn't directly interfered with 聽beyond the large-scale social media bans.

But the bans come at a high cost, the group says.

"The government should protect the openness of the Internet at all times," Mai Truong, program manager of the group's Freedom on the Net project, said in a statement, "not shut it down to limit critical commentary that is vital to democracy."