Five of the 10 spectators injured in the Senior race were kept in Noble's Hospital yesterday evening while four were discharged and one kept under observation.
Emergency services raced to the scene after competitor Johnathan Howarth lost control and crashed near the bottom of Bray Hill.
The race was red-flagged immediately as the spectators and rider were taken to hospital.
One person was reported as suffering 'serious' injuries and was kept under hospital observation last night.
Initial information given to the media said 11 spectators has been taken to Noble's but this was later reduced to 10.
Mr Howarth, who is from Barnsley in Yorkshire, is understood to have escaped the incident relatively unhurt with just a minor fracture.
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