Code Crossword Puzzle

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Across
  1. 2. what you leave behind when you walk (9 letters)
  2. 4. something used to solve a mystery (4 letters)
  3. 5. a person who may have done it (7 letters)
Down
  1. 1. a person who sees a crime (7 letters)
  2. 3. where the diamond was stolen (6 letters)