MIAMI, FEB. 17 -- Anti-Castro militant Orlando Bosch, acquitted last August in Venezuela on charges that he planned the 1976 explosion of a Cuban jetliner, returned Tuesday to the United States, where he was arrested immediately for parole violation.

Bosch was taken into custody by U.S. marshals upon his arrival from Caracas. The parole violation charge stems from his 1968 conviction in a bazooka attack on the Polish ship Polanica here.

Bosch, 61, made a brief appearance before U.S. Magistrate Linnea Johnson, and a preliminary parole hearing was held today. An immediate decision was not expected.

Bosch's attorney, Hank Adorno, said Bosch should be released because he voluntarily returned to face the charges. Adorno said Bosch fled the United States for Latin America in 1974, two years after his parole, because his life was in danger.

"He served 11 or 11 1/2 years in a Venezuelan prison for a crime he didn't commit," Adorno said, referring to the airliner bombing that killed 73 people. "He should be allowed to live as a productive member of the Cuban-American community."

But Adorno said legal technicalities made a quick release unlikely.

"He knew when he came here what he was getting into," Bosch's wife, Adriana, said. "We are confident when it is all over he will be free."

Bosch's arrival was a surprise to Miami's closely knit Cuban community, but initial reactions were positive. "At last the man is free," said Jorge Mas Canosa, head of the influential Cuban American National Foundation, adding that the community's reaction "is one of rejoicing."

Bosch was acquitted in Venezuela of the bombing charges for a third time Aug. 7 and was held in a secret location awaiting an appeal by the prosecution. No appeal was filed in the 90-day limit, and the acquittal stood.

Most of those killed in the blast of Cubana Airlines Flight 455 were Cuban athletes who had competed in Central American and Caribbean Games in Venezuela.

Two Venezuelans were sentenced to 20 years in the bombing. A fourth defendant, Cuban-born Luis Posada Carriles, escaped from jail in 1986 and reportedly was fighting with the contra rebels in Nicaragua.

Bosch served four years of a 10-year sentence in the Atlanta federal penitentiary for the 1968 attack on the Polanica, a Polish freighter engaged in trade with Cuba. The incident prompted an FBI crackdown on militant anti-Castro groups.