An American aid contractor who worked in a US program aimed at undermining Cuba's government has gone on trial in the capital Havana, accused of crimes against the state.
However, no verdict was reached in the trial which was held on Friday and testimony will continue on Saturday, reports Reuters.
Alan Gross, 61, faces a possible 20-year sentence if convicted in a case that halted a brief period of improvement in US-Cuban relations and could damage them for years if Gross is imprisoned for long.
He is accused of supplying Internet equipment, including sophisticated satellite phones, to dissidents in violation of Cuban law.
Gross spoke on his own behalf in the trial, making "a free declaration" and responding to questions from his attorneys, prosecutors and the panel of judges hearing the case, a Cuban government statement said.
Gross and his Cuban lawyers "presented a vigorous defense today," said Peter Kahn, his US lawyer, in a separate statement.
"We respectfully urge the Cuban authorities to free Alan immediately," he went on to say.
The government said other witnesses also testified and evidence from investigators was presented.
Though Kahn attended the trial with the defendant's wife, Judy, Gross' defense is being handled by Cuban lawyers.
US consular officials attended the trial, but neither they nor a US spokeswoman could comment. The foreign press was not allowed in the court.
The United States, at odds with Cuba for more than five decades, said he provided Internet service to Jewish groups but committed no crimes.