Solve the puzzle

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Across
  1. 3. A person who sees an event, typically a crime or accident, take place.
  2. 7. A person who has committed a crime
  3. 8. The unlawful premeditated killing of one human being by another
Down
  1. 1. A claim or piece of evidence that one was elsewhere when a criminal act is alleged to have taken place
  2. 2. A person, e.g. a police officer, whose occupation is to investigate and solve crimes
  3. 4. A person who steals another person's property
  4. 5. A thing designed or used for inflicting bodily harm or physical damage
  5. 6. Take (someone) away illegally by force, typically to obtain a ransom.