Locals block road alleging negligence on part of KSEB as the cause of accident.
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The father and son in the car - Prakash Devarajan, 49, and Shivadev, 11 - are said to have died on the spot near Attingal.
Minister for Transport, Antony Raju said Kerala has been witnessing an increase in racing accidents of late.
One of them had only hours before learnt about his success in the plus-two examinations.
A group of bike riders had been racing in the area since Sunday afternoon.
Vizhinjam's Mukkola is notorious for illegal races by the youth.
The incident occurred in the evening while Joel was returning to his residence in St Helens from Bolton Hospital.
The accident happened around 10 am on Saturday after the safety wall of the premise collapsed.
The injured are being treated at hospitals in Wandoor, Nilambur and Perinthalmanna.
The driver of the car and a passenger were killed in the accident.