When the bailiff opened the door of the cell on Monday, Ms. Torres-Flores was lying on the floor, the deputy said. The cell typically holds prisoners for no more than an hour, measures 9 feet by 10 feet and contains only a metal table with benches that swing out from it. It has a steel door and concrete walls.

“From what I understand  it sounds horrible to say  it was an oversight,” said Nathan Lewis, Ms. Torres-Flores’s lawyer. “No one is walking around there Friday, and she just got left in there over the weekend.”

“There’s no water, there’s no food,” Mr. Lewis added. “She basically said it was really bad.”

She was taken to a hospital and treated, and is now recovering at home, Mr. Lewis said, “very worn out from the whole ordeal.”

Ms. Torres-Flores has been in the United States for 19 years, and her children were born here, though she is in the country illegally, said her immigration lawyer, Roy Petty. Mr. Petty said she had been among numerous people arrested at a flea market on charges related to the sale of pirated DVDs and CDs.

She went to court Thursday for a hearing on a plea agreement over the charges, but decided to plead not guilty. She was then placed in the holding cell for transfer to the county jail, since the new plea was contrary to the terms of her original release on bond. Instead, she was forgotten.