Devon and Cornwall Police have referred itself to the Independent Police Complaints Commission (IPCC).
The force said the two suspects and victim had recently come to the attention of police for an earlier incident but could not go into more detail.
More top news
Police in Wales have found a body in the search for missing Hollie Kerrell from Kingsbridge. A 35-year-old man has been arrested
Persistent rain today especially towards the afternoon.
Possibly clearing up towards the evening.