HAVANA (Reuters) - Opposition activists and independent journalists in Communist-run Cuba said state security and police stopped them from leaving their homes on Tuesday to prevent them marking or reporting on international Human Rights Day.

Some activists had planned to observe the day by calling publicly for the liberation of one of the top opposition leaders in the one-party country, Jose Daniel Ferrer, whom Cuba calls a U.S.-financed counterrevolutionary.

Cuban authorities arrested Ferrer, 49, more than two months ago. While dissidents complain they are frequently subjected to short-term detentions to intimidate them, his is the first long-term arrest of a high profile government critic in years.

Human rights activists say it reflects a broader increase in repression as the country deals with an awakening of civil awareness thanks to expanded access to the internet and a hike in U.S. sanctions.

International rights organizations like Amnesty International, the Trump administration and the European Parliament have called for Ferrer’s release.

“‘Go back up to your flat because today you cannot go out’ said a state security official guarding the entrance of my building,” wrote Luz Escobar, a reporter for the alternative news website 14ymedio, on Twitter.

The Cuban government, which says its critics on human rights overlook Cuba’s guaranteed healthcare and education, did not reply to request for comment.

Cuba says the United States is using Ferrer - with its top diplomat in Havana even abetting his illegal activities - to undermine the government as part of its broader attempt to overthrow socialism in Latin America.

Activists from Ferrer’s Patriotic Union of Cuba called this week for his release and that of other UNPACU members in a campaign on social media.

“There is a continued vigilance as is usual on this day ... as part of a broader police operation to stop actions in favor of Ferrer,” said UNPACU spokesman Carlos Amel Oliva.

The Day of Human Rights coincides with the implementation on Tuesday of a new U.S. ban on all U.S. scheduled flights to Cuban destinations except Havana. Cuban Foreign Minister Bruno Rodriguez said on Twitter this would hurt Cuban families living on either side of the Florida Straits and violated their rights.