Four Haitians were released for "humanitarian reasons" from a Navy brig in Brooklyn today after more than 15 months' imprisonment.

Carrying suitcases bearing their few belongings, the four stepped out of the immigration detention center into the sun. "I feel better now! Very very good!" said Slvie Thigene, 24. One of several Haitians held at the center who speak English, she had finished college in Haiti before attempting to flee to the United States.

The Haitians released today are among 49 who have been detained here by the Immigration and Naturalization Service pending hearings on their asylum petitions. Immigration officials have argued that the Haitians should remain in custody because otherwise they might disappear and remain in the country illegally.

Earlier this year, a Justice Department spokesman, Art Brill, explained, "The rules say that if illegal aliens come to this country without proper documentation they will be detained . . . . All we're trying to do is to regain control of our borders."

Almost 1,900 other Haitians who arrived in the United States at about the same time have been released from detention camps in Florida because a federal district court ruled in June that they must be paroled pending their hearings because the government had violated its own procedures in incarcerating them.

The Brooklyn Haitians, however, were not included in the order because separate litigation had been filed on their behalf in New York City and the case had been lost. The government recently yielded for "humanitarian reasons," however, and 19 of the original 49 in Brooklyn have been released.

The Haitians released today were met at the door by their attorneys, their personal sponsors and representatives of voluntary agencies who have been seeking their freedom.

Sue Susman, an attorney with the Columbia Law School Immigration Law Clinic, who has helped represent a number of the Haitians, stood in the doorway hugging each of them as they emerged.

"I think it should have happened a long time ago," she said. "The government has spent about $30 for each person each day, keeping them locked up when they aren't dangerous, and there's a community out there waiting to support them."