A street-cleaning water bowser rammed into the side of a bus in Sham Shui Po this afternoon in a freak crash that injured 23 passengers, aged 5 to 85, and the passenger of the truck.

According to video circulating online, the driver of the truck, who police named as Mr Wong, 64, lurched straight into the passing bus from a standstill, leading to questions over the cause of the accident. Police say the crash happened at around 4.20pm at the junction of Yin Chow Street and Kweilin Street, an area packed with Saturday afternoon shoppers.

Police arrested the driver for dangerous driving – a police source says he is still being held as at 11.20pm on Saturday night.

The bus driver, 59-year-old Mr Pau, was uninjured. Fire services and ambulances took all victims conscious to nearby hospitals.