BY ELAINE DE VALLE

  Thirty Cuban migrants intercepted by the Coast Guard five miles from Sugarloaf Key -- and thrown into the sea when their smuggler's boat capsized -- were taken back to the Communist-ruled island Sunday, the Coast Guard said.

  Relatives and activists did not know the Cubans had been repatriated when they gathered in Little Havana Sunday to protest what they said was the use of excessive force to stop them. They were joined by Norci Fraga, 33, and son Yerany Rivero, who had been aboard the boat but were taken to Mariners Hospital in the Keys when the 17-year-old hit his head.

  ''Everyone fell into the water,'' Fraga said. ``We were fine and when the helicopter arrived is when the waves started batting the boat. Then two boats arrived, and they tossed ropes into the motors. They pointed rifles at us. They slammed into us.''

  Coast Guard Petty Officer Danielle DeMarino said the migrants are lucky that rescuers were there when the boat capsized about 11 a.m. Friday.

  ''What caused the capsizing is that it was grossly overloaded,'' DeMarino said, adding that the 30 migrants and two suspected smugglers -- who were arrested -- were on a 29-foot boat.

  ''Everyone panicked [when the Coast Guard arrived] and went to the rear of the vessel, and any slight shift when you're talking about such an overloaded vessel can cause it to capsize,'' DeMarino said.

  She also denied that rescuers used excessive force.

  In the past three years, at least 160 Cuban migrants have died or disappeared in botched smuggling operations, DeMarino said.

  ''That's what we know of,'' she said. ``It's probably safe to assume that there are more . . . that we don't know of.''

  But relatives and their attorney, Irving Gonzalez, want to see a video the Coast Guard may have made of the interception.

  Ramón Saúl Sánchez, founder of the Democracia Movement, said it was one of the agreements the agency made after community outrage over the so-called Surfside Six incident, in which pepper spray was used to keep six rafters from reaching dry land and staying in the United States.

  DeMarino said she would probably release the ''chase video'' today, if a camera recorded the incident.