NEW YORK - Nine Nobel laureates, including the South African campaigner Desmond Tutu and the German novelist Günter Grass, join forces today with more than 100 celebrities from the arts, law and media to protest against the US government's detention of five Cubans for allegedly spying on behalf of the Cuban government.

The so-called Miami Five were sentenced in 2001 to prison terms of between 15 and 25 years for allegedly acting as Cuban agents within the exile community in Miami. The men and their supporters said they had come to the US to infiltrate and disrupt rightwing exile groups perpetrating acts of terrorism within Cuba.

To mark the 10th anniversary of the arrests of Gerardo Hernández Nordelo, Ramón Labañino, Antonio Guerrero, Fernando González and René González, full-page adverts are being taken out in the Guardian and the Independent newspapers. They claim the men were unjustly jailed, and protest against the refusal to allow the wives of two of the prisoners to visit them from Cuba for up to 10 years.

Signatories to the adverts include the designers Vivienne Westwood and Jasper Conran, artist Howard Hodgkin, writers Iain Banks and Harold Pinter, and actors Julie Christie and Susannah York.

The case of the Miami Five has attracted the attention of international human rights groups. Amnesty International has repeatedly raised the issue with the US government. The UN working group on arbitrary detention has also found that the US failed to give the men a fair trial.