The coroner has indicated she is likely to give a narrative verdict on the death of seven-week-old Axel Peanberg King.
Dr Shirley Radcliffe told the inquest that she had been unable to find any evidence to suggest a "clear cause" of death.
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Essex Police has become one of only four forces to use polygraph testing to help manage the risk posed by convicted sex offenders.
Two members of the public were injured along with two police officers who were in the unmarked vehicle.
Scotland Yard recorded 1,235 Islamophobic attacks in the last 12 months, compared with 811 in 2015.