WASHINGTON, May 21 — The F.B.I. accused Representative William J. Jefferson, Democrat of Louisiana, on Sunday of taking hundreds of thousands of dollars in bribes from a Kentucky businessman and stashing $90,000 from the scheme in his home freezer in Washington. The accusations appeared in court documents that were made public only hours after a team of 15 agents from the Federal Bureau of Investigation completed an all-night search of Mr. Jefferson's Congressional offices. F.B.I. officials said the raid, which began about 7:15 p.m. Saturday and ended early Sunday afternoon, was the first the agency had ever conducted at a...