By ROBERTO FABRICIO

At 81 he sports a full head of silvery hair; his deep green eyes gleam, attentive to every move, and his handshake is firm and determined.

"They can jail me, they can take my weapons away and they can even kill me, but they will never defeat me," Zacarias Acosta said at the storefront that serves as his home and headquarters.

Late Friday he and his 48 year-old son, Roberto were arrested with a cache of weapons that included a bazooka, a 20-mm cannon, dynamite, 42 incendiary devices, four bombs and ammunition. They were charged with possession of unregistered firearms.

Saturday, a sad and dejected Zacarias Acosta looked back on his life - a life that included the mayorship of Regla, a fishing town across the bay from Havana - and decided that he doesn't understand the world anymore.

"The weapons belong to anti-Communist Cuban patriots," Acosta said. "Some of those weapons were left behind by patriots that infiltrated into Cuba and were arrested. Some of those weapons were given to us by the U.S. agents years ago when they were trying to aid our revolution against Castro."

"Now I don't understand the Americans anymore," he said. "Look at the way they are treating their great President, like if he was their enemy."

"If they are doing that to him, what can we poor Cuban exiles expect? Nothing; we will get no aid to help our country, now I am convinced," he sighed.

Treasury agent Mike Hall said the Acostas were arrested after an investigation by his department that led to the "Batallon Antonio Maceo" offices at 3460 NW 17th Ave., where the elder Acosta has lived for the last 10 years. Agents seized the weapons.

At his son's home at 3069 NW 26th St., agents found the rest of the cache, including 15 sticks of dynamite, four rounds of bazooka ammunition, four home-made bombs, a 20-mm cannon, 137 rounds of cannon ammunition and 1,000 rounds of assorted ammunition:

The elder Acosta said his son was not aware he was using a small utility room to store the weapons and is sorry Roberto was arrested. Both were released on a $5,000 bond.

Zacarias Acosta has for several years been the ranking officer of the Batallon Antonio Maceo - named after the Cuban general slain by the Spaniards in 1898.

Most of the organization's members are former Cuban military men in their 60s and older.

"We will never give up hope of freeing our country from the Communist yoke," Acosta said. "After all, our hope for a final liberation is all we have left, because in reality we have lost the Fatherland. But we will never lose our faith in freedom."

He said he and several dozen members of his organization were captured by a British frigate off the Bahamas in 1963 as they were on their way to stage a commando raid on Cuba.

A few years ago he said he was arrested in Miami Beach as he and other exiles protested the showing of the movie "Che," depicting the life of Communist revolutionary Ernesto (Che) Guevara. He said Friday night they

were playing dominoes when the federal agents served their warrants.

"We have never harmed anyone here," he said. "We have always wanted to fight communism and that is why we kept the weapons, so at the first chance we have we can go back and fight it."

"So what does this country do?" he asked. "They come and take the weapons from us - it allies, while they go around signing treaties with the Russians and the Chinese - its enemies."

"They have this word, 'detente,' for it," he said: "In Spanish, 'detente' means `to stop,' and I think the Americans are just stopping themselves."