Baron had been paired with his handler for the last four years. Essex Police says they had made many arrests together:
He was injured and taken immediately to a veterinary practice but sadly he had to be put to sleep.
The circumstances surrounding this tragic incident are currently being reviewed.
Baron's handler and family are understandably very upset.
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The terror attack carried out by Khalid Masood at Westminster that left four people dead lasted less than two minutes say police.
Two knives were found at the scene in Islington, North London, and the suspects fled on foot before being arrested.
The family of the police officer who was murdered in the Westminster attack have thanked those who were with him 'in his last moments'.