The judge ordered Karsan held even though his friends posted $250,000 cash bail earlier this week. Ambrecht said Karsan, a native of Turkey, is a flight risk because he has ties abroad and there are unresolved questions about his immigration status.

Assistant District Attorney Anne Schwartz told Ambrecht that Karsan is in the country illegally. Immigration officials issued a warrant yesterday to detain Karsan while they decide his status.

Karsan, of Amityville, N.Y., was arrested last Wednesday. He was accused of threatening to release embarrassing tape recordings and candid photographs of Ono, the widow of John Lennon, and possibly have her killed unless she gave him $2 million.

Karsan warned Ono that he had people "on standby waiting to kill her" if she crossed him, prosecutors said.

Defense attorney Robert Gottlieb said Karsan entered the United States legally from Turkey in 1992 on a work visa. "He has worked nonstop since then to get a green card (for permanent resident status)," the lawyer said. "The question is whether that was resolved properly."

Gottlieb told the court today that the immigration lawyer Karsan had hired turned out to be a fraud and has since died. So Karsan doesn't know where his immigration status stands, Gottlieb said.

Karsan is accused of handing Ono the extortion letter on Dec. 8, the 26th anniversary of John Lennon's death.