By JUAN O. TAMAYO
Herald Staff Writer

At least one bomb exploded and two others were deactivated in tourist hotels in Havana and Varadero in the first such incidents reported in Cuba since the early 1960s, five knowledgeable sources said.

Since the April incidents, authorities have tightened security at Havana's Jose Marti Airport for arriving international flights and are interrogating four detained Cuban dissidents, according to airline passengers and relatives of the dissidents.

Cuba's official news media and foreign journalists based in Havana have reported nothing on the bombs, and Foreign Ministry officials have refused to comment on repeated questions from correspondents over the past two weeks.

Cuba experts speculated that the bombs could be the work of Castro opponents, solitary madmen or even Cuban security agents trying to manufacture an excuse for a crackdown on dissent.

Although many details of the bombs remain shrouded in secrecy and rumors, five sources in Havana and elsewhere, including one U.S. official, said they had reliable information confirming at least three bombs.

The sources said one exploded at dawn April 12 in a bathroom of the discotheque at the Hotel Melia Cohiba, a 20-story tower that is Havana's top hotel and draws the richest foreign tourists and business people. The hotel is operated by the Spanish Melia chain.

A second bomb was found later the same day in one of the hotel's upper floors, all the sources agreed. Two sources said the bomb was turned in by a foreigner who lost his nerve as he tried to arm it, and one of the sources said the man had been identified as a U.S. citizen.

Dissident Cuban journalists reported on the blast the same day, quoting neighbors as saying the unexplained explosion had destroyed part of the disco and shattered hotel windows.

Melia chain officials in Spain have said the explosion was caused by a burst pipe. Cohiba Manager Carlos Vellota did not return phone calls from The Herald.

Four of the sources said they had credible reports that a third bomb had either exploded or been deactivated soon after the Havana incidents in a hotel in the resort of Varadero, 60 miles east of the capital. No injuries were reported in any of the incidents.

Dissidents detained

Cuba's political police detained four dissidents three weeks after the Cohiba blast and have been questioning them, in part about the bombs, at their headquarters in a former seminary known as Villa Marista, relatives said.

The dissidents -- Argileo Cancio Chung, Lorenzo Pescoso, Alberto Pereira and Jesus Perez Gomez -- have denied any role in the incidents, relatives say. They are members of the Peace, Progress and Liberty Movement and the National Action Party, both of which advocate peaceful change in Cuba.

Cuba experts say the last bombings they recalled in Cuba go back to the early 1960s, when opponents of Fidel Castro's turn to communism launched a quickly defeated campaign of sabotage against his regime.

In late 1991, Cuban police arrested three Miami exiles who infiltrated the island with guns and hand grenades and accused them of planning to bomb government offices and movie houses. One was later reported executed, and the other two are serving 30-year prison terms.

The following year, Miami exiles claimed responsibility for a seaborne machine-gun attack on a Varadero hotel as part of a campaign to scare tourists and keep them from vacationing in Cuba.

Word of blast spread

The Cohiba explosion apparently caused little stir at first, but word of the bombs has now spread throughout Havana and raised three separate lines of speculation on who might be responsible.

One source said Cuban authorities have evidence of links to Cuban exiles in the United States who want to create panic in the Cuban capital, drive tourists away and shake up the Castro government. That report was not confirmed by any of the other sources.

Longtime Cuba-watchers outside the island, including U.S. officials, raised the possibility of a lone bomber, either deranged or bent on a quixotic campaign against the Castro government.

But they also cautioned that the bombs could be part of a campaign by Cuban authorities to stage incidents, blame exiles or U.S. agents, and then impose tough security measures.

There are precedents for such speculation.

In 1992, a Cuban diplomat at the United Nations in New York was expelled after he was videotaped offering money to a member of the Miami-based Alpha 66 group to finance armed attacks on Cuba. The Alpha 66 ``member'' turned out to be working for the FBI.

And just last year, Juan Pablo Roque, the Cuban who worked with Brothers to The Rescue before he returned to Havana, was urging Brothers pilots to be more aggressive just before Cuban MiGs shot down two planes. Roque is widely believed to have been a Cuban spy.

Castro and the Communist Party have launched a strong anti-American campaign in recent months, accusing Washington of stepping up efforts to topple the regime and defiantly vowing to defend the revolution to the end.

``The timing of these bombs is awfully convenient for them,'' said one U.S. official.

Copyright © 1997 The Miami Herald