The group are shouting and swearing and the frequent sounds of breaking glass can be heard.
Two young people were arrested as a result of the attack and vandalism – one charged with assault, trespassing and shoplifting and the other referred to Youth Aid.
A police spokesperson said the attack was concerning.
"As a result, police will have an increased presence in the CBD area, including around the shopping complex, to alleviate any concerns the public may have."
Morgan Lambert, who owns the cafe Nourish says the attack happened very close to his store.
"They targeted the shop next to me, attacked the staff, it's all family members in the shop, they've been attacked. [The offenders] were jumping on counters, smashing vases, anything they could use as a projectile they used as a projectile.
"It was pretty horrific."
Lambert says the staff were hit, kicked and had things thrown at them. His own staff were hit by the remnants of broken glass, but avoided injury.