International Monetary Fund (IMF) chief Dominique Strauss-Kahn appears in Manhattan Criminal Court during his arraignment in New York, in this May 16, 2011 file photograph. [Photo/Agencies]

Late on Wednesday, Dominique Strauss-Kahn resigned as managing director of the International Monetary Fund, according to a letter released by its executive board.

In the letter, Strauss-Kahn denied the allegations but said he felt compelled to resign with "great sadness" because he was thinking of his family and also wanted to protect the IMF.

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Strauss-Kahn, jailed at Rikers Island since Monday, made a second appeal for bail earlier Wednesday and proposed to be confined to his daughter's Manhattan home 24 hours a day with electronic monitoring. He was set for another hearing Thursday afternoon.

The French politician said in court papers that he had surrendered his passport and wouldn't flee the country. "I do not intend to leave the United States of America without the permission of the New York Court," he said.

Besides examining the Sofitel Hotel suite for further potential DNA evidence, investigators were looking at the maid's keycard to determine whether she used it to enter the room, and how long she was there, officials said.

One of the officials said that the DNA testing was being "fast-tracked" but that the results could still be a few days away.

The two officials spoke to the AP on condition of anonymity because neither was authorized to speak about the case publicly and because it has gone to a grand jury.

The maid, a 32-year-old immigrant from the West African nation of Guinea, told police that the 62-year-old Strauss-Kahn came out of the bathroom naked, chased her down, forced her to perform oral sex on him and tried to remove her underwear before she broke free and fled the room.