Police are investigating separate incidents where two boys were robbed and another was stabbed by a group of people on motorbikes in Bertram and Baldivis.
Detectives say two 14-year-old boys were riding their electric scooters on Mortimer Road around 9.40pm on Saturday when they were confronted by three males on motorbikes.
During the confrontation, the victims were threatened with a knife and their scooters were stolen.
A short time later, about 11.30pm, three teenage boys were walking along Safety Bay Road when they were approached by a group of males on motorbikes and scooters.
A fight broke out, during which time one of the males suffered stab wounds to his abdomen.
"A 16-year-old male juvenile was dropped off at Rockingham Hospital by two unknown males on motorbikes," a WA Police spokesperson said.
Detectives are seeking CCTV and dashcam vision of the below locations:
- Mortimer Road and Kwinana Freeway, Bertram between 9.30pm and 10pm
- Safety Bay Road and Baldivis Road, Baldivis between 10.15pm and 11.15pm
- Rockingham General Hospital, around Elanora Drive, between 11.30pm and 12.15am
Anyone with information in relation to these incidents is urged to contact Crime Stoppers on 1800 333 000 or report online via www.crimestoppeswa.com.au.
People reporting information to Crime Stoppers may remain anonymous if they wish.
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