The hacktivist group Anonymous has announced it will mark the 100th day of the Guantanamo hunger strike with three days of massive protests, calling on supporters to join their global action both on the ground and online.

“We stand in solidarity with the Guantanamo hunger strikers. We will shut down Guantanamo,” Anonymous’ online statement reads.

The group did not detail how it is would achieve this goal, but promised “twitterstorms, email bombs and fax bombs” would be part of its anti-Gitmo efforts. The group said mass protests would take place from May 17 to 19.

The group’s online call for action condemned the US for failing deliver on President Obama’s promise to shut down the facility. The group described the prison as a concentration camp, and said that many of the inmates are being kept there despite having been cleared for release. Anonymous also lashed out at the Guantanamo administration for force-feeding some of the hunger-striking prisoners, which the UN recently condemned as torture and in breach of international law.

Anonymous also expressed indignation over how the facility, which they called a “disgrace for any civilized country,” is one of the most expensive prisons in the world, costing $900,000 annually to house each prisoner.

“Guantanamo Bay must be closed at once, and the prisoners should be either returned to their home countries or given a fair trial in a federal court. Guantanamo Bay is an ongoing war crime. Anonymous will no longer tolerate this atrocity,” their statement said

The Anonymous website also posted phone numbers for the White House, US Southern Command and the Department of Defense, urging supporters to ‘phonebomb’ officials with calls about Guantanamo.

Inmates at Guantanamo went on a hunger strike at the beginning of February over alleged mistreatments, including the mishandling of their Korans. Currently, more than 100 inmates are refusing food, two dozen of whom are being force-fed.

‘Anonymous’ is notorious for its politically motivated cyber-attacks. A recent hack attack took down the Spanish parliament’s website in late April, the same day mass anti-government protests were held in Madrid.

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