Northeast district police chief Soffian Santong said the incident occurred at 10.30pm when the five-tonne lorry, laden with furniture, was heading towards Gelugor from Bayan Lepas.

“The vehicle strayed into the opposite lane and rammed into the five vehicles at the traffic light junction,” Soffian said today.

The injured included the 32-year-old driver of a Volkswagen Polo and the driver of a Honda Jazz, aged 40. A 12-year-old passenger in the Honda Jazz suffered a sternal fracture. The drivers of a Mercedes Benz and a Honda Stream escaped unhurt.

Soffian said police were trying to identify a motorcyclist who was injured and had been sent to a nearby private hospital for treatment.

Police found dried leaves believed to be cannabis in the glove compartment of the lorry, and a bottle containing liquid suspected to be ketum water hidden at the back of the passenger seat.

The lorry driver, aged 28, and his assistant tested positive for cannabis and have been remanded three days to help in the investigations.