Two teenagers have appeared in court following an alleged rampage through the Smart Street Mall in Mandurah at the weekend.
Police allege the accused were in a barber shop at the mall around 11.25am on Saturday when their friend became involved in an altercation at another location.
"It will be alleged the youths exited the shop, one armed with a hatchet and the other a hammer, " a WA Police spokesperson said.
"They allegedly walked through the mall, shouting and looking for the person involved in the altercation with their friend.
"Police attended the scene and seized a bag which contained the hatchet and hammer."
A 17-year-old boy suffered serious injuries and was rushed to Royal Perth Hospital but it is unclear how he received those injuries or who was responsible.
A 15-year-old boy from Pinjarra and a 16-year-old boy from Coodanup appeared in the Perth Children's Court on Sunday each charged with being armed in a way that may cause fear.
They were both remanded in custody at Bankia Hill.
The investigation is ongoing.
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