Cuban courts sentenced Alan P. Gross, an American Jewish contractor, to a 15-year prison term for "subversive activities" against the state on Saturday.
Gross, 61, was convicted of "acts against the independence and territorial integrity of the state" for setting up Internet networks for "dissidents" using "sophisticated" communications technology, Reuters reported.
Sources familiar with his work, who asked to remain anonymous, said Gross was helping Jewish Cubans download music and information on Wikipedia and the Encyclopedia Britannica from flash drives, the Washington Post reported. He wanted to help Cuba's small Jewish community communicate with one another and with Jews in other countries, the sources said.
The Obama administration said the sentencing "adds another injustice" to his ordeal, which began with his arrest on December 4, 2010.
"He has already spent too many days in detention and should not spend one more. We urge the immediate release of Mr. Gross so he can return home to his wife and family," National Security Council spokesman Tommy Vietor said in statement..
The World Jewish Congress (WJC) compared the sentencing to human rights' violations in the Middle East.
"[This is] another miscarriage of justice by an oppressive regime just miles from America's shores," Dan Diker, secretary-general-designate of WJC said.
Gross was employed by Development Alternatives, Inc., (DAI), headquartered in Bethesda, Md., which Cuban authorities described as "American intelligence services" because it contracts with the U.S. Agency for International Development.
"Alan is a social worker by training and a dedicated international development professional with 25 years of experience delivering humanitarian assistance to people in some 50 countries and around the world." DAI President James Boomgard said in a statement.
Cuban authorities initially arrested Gross for entering the country without the proper visa and delivering satellite phones to the Jewish community.
At the time of his arrest, U.S. officials said he'd gone to Cuba as part of a government program to provide communications equipment to nonprofit Jewish organizations.
Following several visits to Cuba to deliver computer and satellite equipment, his follow-up trip in December was reportedly to evaluate how people were making use of their computers, according to sources close to him.
Some analysts have speculated that Havana wants to use Gross as a bargaining chip for the release of five Cubans convicted of spying and serving lengthy prison terms.
The Jerusalem Post contributed to this report.