Human rights activists and the U.S. government condemned Cuba for sentencing critics of the regime to long prison terms in a crackdown that showed communist leaders were more worried about internal control than international contempt.

Fidel Castro's government sentenced activists, journalists and an economist to up to 27 years in prison Monday for allegedly collaborating with U.S. diplomats to undermine the socialist state.

"We are witnessing the harshest political trials of the past decade," said veteran human rights activist Elizardo Sanchez, one of the few leading opponents of the regime not arrested after the crackdown began last month.

Sanchez's non-governmental Cuban Commission on Human Rights and National Reconciliation said prosecutors originally sought life sentences for a dozen of the dissidents, among 80 facing closed trials that began Thursday.

It was unclear how many dissidents have been sentenced so far, but activists have been unable to confirm any life sentences. The shortest sentence was 15 years.

"The Castro government is persecuting journalists for acting like journalists," State Department spokesman Philip Reeker said. "They're persecuting economists for acting like economists, and peaceful activists for seeking a solution to Cuba's growing political and economic crisis."

The longest sentence confirmed by Monday was 27 years for independent journalist Omar Rodriguez Saludes. A familiar figure in the dissident community, Rodriguez Saludes often rode his bicycle to news conferences, a camera dangling from a strap around his neck.

Opposition political party leader Hector Palacios, among those originally recommended for a life sentence, received 25 years, said his wife, Gisela Delgado.

Palacios is a leading organizer of the Varela Project, which gathered more than 11,000 signatures supporting a referendum on new laws guaranteeing civil liberties such as freedom of speech and private business ownership. The island's parliament shelved the request.

Palacios was among the dissidents who met with former President Jimmy Carter, who visited the island in May and used a live speech to the Cuban people to bluntly describe the country as undemocratic and to publicize the Varela project.

"This is an injustice," Delgado said after learning of her husband's sentence Monday morning. "We are as Cuban as members of the Communist Party."

The communist government accuses the dissidents of being on Washington's payroll and collaborating with U.S. diplomats to harm Cuba and its economy.

Jose Miguel Vivanco, of Human Rights Watch, urged the United Nations Human Rights Commission meeting in Geneva to condemn Cuba for the sentences.

In Stockholm, Swedish Foreign Minister Anna Lindh warned that the crackdown could hurt Cuba's prospects for more cooperation with the European Union.

"The mass arrests of dissidents that have taken place lately are one more example of the human rights violations being committed in Cuba," Lindh said.

The crackdown, which ended several years of relative tolerance, began when Cuban officials criticized the head of the American mission in Havana, James Cason, for actively supporting the island's opposition.

"This is an attempt for them to squash down and put the policemen back in the person's head that many of the Cubans were getting out of their head," Cason said Monday in a speech at the University of Miami in Coral Gables, Fla.

Cason denied accusations that the U.S. mission had local dissidents on its payroll, saying the mission operates no differently than embassies in other countries.

The last trials reportedly wrapped up Monday, with all sentences expected by week's end.

Also sentenced Monday was independent journalist Raul Rivero, who received the full 20 years prosecutors sought, said his wife, Blanca Reyes.

"This is a crime for a man who has only written the truth," Reyes said.

Dissident economist Marta Beatriz Roque and independent journalist Oscar Espinosa Chepe each received 20-year sentences, their relatives said.