By Don Bohning and Margaret Carroll

Four members of a militant anti-Castro exile group that claimed it was planning to seize and burn a Cuban ship were ordered Friday to appear for a preliminary federal hearing Tuesday on charges of illegally exporting arms.

Customs agents swooped down on the four late Thursday as they chugged out of Biscayne Bay through Government Cut in an 18-foot boat equipped with a 20-mm cannon and an automatic rifle.

Jailed were Jorge Gonzalez, 26; Barbaro Balan, 31; Marcos Rodriguez, 28; and Francisco Garcia, 26.

In a brief appearance Friday before U.S. Commissioner Edward P. Swan bond was continued at $5,000 each. A preliminary hearing was rescheduled for 2:30 p.m. Tuesday to give them a chance to consult an attorney. Dr. Orlando Bosch, chief of a local exile activist group, claimed the four had been part of a plan to seize and sink the Cuban freighter 26 de Julio.

The vessel was believed en route back to Cuba after a widely publicized incident off the Virginia coast Tuesday in which three crew members tried unsuccessfully to gain political asylum in the U.S.

Bosch said the plan had been to rescue the three crew members from the vessel then set it afire. He claimed a second boat with six other exile activists aboard also had been part of the plan, broken up when Customs agents seized the 18-footer.

Some exile sources speculated, however, that the entire incident had been staged as an effort to gain publicity for the exile group and that there had been no second boat.

Bosch and the Insurrectional Revolutionary Recovery movement - Commandos L alliance have claimed raids in the past against Cuba which have never been confirmed by either the U.S. or the Castro Government.

Balan and Rodriguez, two of those arrested Thursday, were both involved with Bosch when he was indicted in 1967 for heading a group which said it planned to bomb Cuba-bound shipping.

The charges were dropped because the government said it couldn't rely on its chief witness.

Balan also was arrested in January of 1967 as part of an abortive Haitian invasion attempt headed by Rolando Masferrer, onetime aide to Cuban dictator Fulgencio Batista. Charges were dropped against Balan and several others. Masferrer was sentenced to four years in prison earlier this week.