NEW YORK - A man found guilty 17 years ago of murdering his parents as a teenager was freed from prison yesterday, days after a court overturned the conviction and ordered a retrial because of new evidence.

Martin Tankleff, 36, was released on $1 million bail. He thanked his friends, supporters, and witnesses who came forward "because it was the right thing to do."

An appeals court threw out the 1990 conviction last week, saying new evidence suggested that someone else might have killed Seymour and Arlene Tankleff in their Long Island home.

"I was as upset when Marty was convicted as I was the day I learned that there were murders," said his aunt, Mary Anne McClure. "Now we can mourn my sister properly, because we haven't been able to for 19 years."

Martin Tankleff was 17 when his parents were bludgeoned and stabbed in their Belle Terre, N.Y., house in 1988. After a detective falsely told him that his father had awakened from a coma and implicated him, Tankleff wondered aloud whether he might have "blacked out" and committed the crimes, and he confessed to them. But he quickly withdrew the confession, refusing to sign a statement police had prepared.

He was sentenced to 50 years to life in prison after being convicted in one of the nation's first televised trials.

Private detectives working on Tankleff's behalf later turned up witnesses who implicated a business partner of his father's and others in the killings. The partner, Jerry Steuerman, was never charged and has denied involvement.

The Appellate Division of state Supreme Court in Brooklyn said it was probable that a new jury would render a different verdict if given a chance to hear all the evidence now available.

The case had raised questions about coercive interrogation tactics and drew the support of the Innocence Project, a group dedicated to exonerating wrongfully convicted people. "It's a great day for justice in New York and in the country generally," said Barry Scheck, the project's executive director.

Suffolk County District Attorney Thomas Spota did not say whether he would seek to prosecute Tankleff again.