Cuban police have prevented the mothers and wives of detained dissidents from marching on the outskirts of Havana, the capital, forcing them into buses and taking them away, witnesses say.
The so-called Ladies in White were heckled by hundreds of
government supporters as they marched with the mother
of Orlando Zapata, who died in a prison hunger strike in February.
As the women began their march on Wednesday, hundreds of pro-government supporters crowded around them, shouting "Long Live Fidel!" and "Get out, worms!"
The government said the hecklers acted spontaneously as a result of disgust with the women, but some believe the government organises them and that many of those taking part are members of state security.
The AFP news agency reported that police arrested the 30 women.
"We are protesting peacefully and we are not going to get on the bus of a government that has kept our family members in prison for seven years," Laura Pollan, the leader of the group, said before being forced onto a bus.
Reyna Luisa Tamayo, Zapata's mother, said that her son had been tortured in prison and that his death on the 85th day of a hunger strike amounted to "premeditated murder".
The Ladies in White have staged marches every day this week to mark the anniversary of a 2003 government crackdown that resulted in 75 opposition activities being jailed, 53 of whom remain behind bars.
Cuba's human rights situation has been a cause of renewed international tension since Zapata's death.
Another man, Guillermo Farinas, has refused to eat or drink since shortly after Zapata's death, though he is allowing himself to be fed intravenously periodically at a local hospital.
The European parliament last week voted overwhelmingly to condemn Cuba for
Zapata's death, and a group of artists and intellectuals have begun to circulate a petition criticising the Cuban government's actions.
And on Tuesday, the human rights group Amnesty International called for the
release of all political prisoners.
Cuba has rebuffed the criticism, saying it will not give in to pressure or blackmail. The government describes the dissidents as common criminals who it believes are paid by the US to destabilise the government, saying every country should have the right to jail traitors.