By Martha Graybow

Other packages contained diamond Cartier and Tiffany watches as well as a diamond bracelet, gold watch, four diamond brooches and a jade necklace, the government said, offering new details of what they described as Madoff's attempt to obstruct justice.

Prosecutors said Madoff should be immediately jailed because he is now a flight risk. The government wants a federal magistrate to place him in custody.

"The need for detention in this case is clear," prosecutors from the U.S. Attorney's Office in New York wrote. Madoff's continued release "presents a clear risk of further obstruction of justice."

Madoff, who is under house arrest in his luxury Manhattan apartment, was arrested last month and charged with what authorities say was an investment scam that bilked clients of as much as $50 billion.

The government did not initially oppose the release of Madoff on bail, but said at a hearing on Monday that circumstances had changed after it learned of the jewelry transfers.

Madoff's lawyer, Ira Sorkin, said at the hearing that the transfers were innocent mistakes by Madoff and his wife, and that most of the items had been returned. He said Madoff was not a flight risk, saying he was under 24-hour security, that Madoff and his wife had surrendered their passports and their bank accounts have been frozen.

U.S. Magistrate Ronald Ellis is weighing the government's request. At Monday's court hearing, where Madoff was present, the magistrate heard arguments from both sides, and asked for additional written filings.

"Our response to the government will be in our court papers," due later Wednesday, Sorkin said.

Prosecutors contend that Madoff violated a court order barring him from concealing or disposing of his assets by, together with his wife, Ruth, sending multiple packages containing valuables to relatives and others.

Prosecutors argued that Madoff posed a serious flight risk, saying the former investor "has assets that cannot be effectively restrained" and that his ties to New York have been largely severed following his arrest.

The government also said that the scope of Madoff's alleged crime was vast, involving thousands of victims, and that it is clear "that the defendant does not have sufficient assets to make those victims whole."

Madoff could again appear in court on January 12, although it is not certain that a hearing will occur on that date. The government had until 30 days from Madoff's December 11 arrest to bring an indictment against him or decide to continue the case for now as a criminal complaint.

(Additional reporting by Grant McCool)

(Reporting by Martha Graybow; Editing by John Wallace and Brian Moss)