Yellow ribbons in Cuba raise awareness for the "Five" HAVANA Thursday was the 15th anniversary of the arrest of five Cuban intelligence agents in the United States. Cubans marked the day with a massive display of yellow ribbons, concerts, marches and political events to demand their release from U.S. prisons and raise awareness about the case. They popped up all over the country. In windows, doorways, over the entrances to cafeterias and hotels, on the iconic lighthouse guarding the Bay of Havana: yellow ribbons for "the Five," five heroes for Cubans serving long prison terms in the United States for spying. "We want the world to know," said Rene Gonzalez, an ex-Cuban intelligence agent, "that the Cuban people as a whole is waiting for their sons which are, have been in prison for 15 years for defending the country. It's a noble thing. Any people would defend themselves when they are in prison for protecting the country, for protecting their own people against terrorism. An image of the "Five," five Cuban intelligence agents in America who were arrested in 1998 and serving long prison terms for spying. Gonzalez, who spent nearly 23 years in the U.S., 13 of them in prison, is the only one of the so-called Cuban Five to have completed his prison sentence and who the U.S. allowed to return to the island last May. The 56-year-old, who began his career as a spy by posing as a defector, is one of the main faces of the current campaign to win the release of his four compatriots remaining in U.S. prisons. President Raul Castro made a rare public appearance at a Wednesday evening concert to throw his weight behind the demand for Washington to release the remaining four Cuban agents. The issue from Havana's point of view is a major sticking point in U.S.-Cuba relations -- and one they insist has not received an adequate hearing in the United States. "Unfortunately this was a long trial which dealt with terrorism, dealt with espionage," said Gonzalez. We had witnesses for the defense from the White House Staff to Generals of the U.S. army and the U.S. people wasn't informed about the trial. And it's been 15 years and the silence still continues and we hope that we are sending a message to the American people now that we are still waiting for our sons and we need them to know about the case. Gonzalez and the Cuban government believe the Five were railroaded and unjustly sentenced for spying when all they were trying to do was prevent bombings and other acts of terrorism against the island. That's the message they're sending to the American people and the symbol of the yellow ribbon to welcome loved ones home is an image they hope will resonate with the American public.