The suspect and the child involved in the accident in Wainiyabia, Navua that claimed the lives of three children and a woman are still admitted in stable condition.
Police Spokesperson, Ana Naisoro confirms the suspect is expected to be questioned once he is medically cleared.
Police have also confirmed that marijuana was discovered in the car.
Naisoro says the dried leaves were tested and the results are positive.
More details will be released later.
The four victims were passengers in the car.
The family residing in Kinoya were travelling to Sigatoka to attend a social function.
Police say the suspect who is the woman's defacto husband was allegedly driving at a high speed when he failed to negotiate a bend resulting in a head-on collision with a bus.
The post mortem examination of the four victims will be conducted soon.
Investigations continue.
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