Police monitored activity on Facebook and other social networking sites to track two rival groups of young men who clashed at the Mt Druitt Westfield shopping centre at 7:45PM on Thursday.
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A massive brawl between rival groups of teenagers and young men at a western Sydney shopping centre was sparked by a war of words on Facebook, police allege. Around 100 young males, aged in their teens and early 20s, had armed themselves with baseball bats and homemade weapons but were met by around 65 police from the dog squad, the riot squad and other specialist officers.
Thirteen of the males, aged 16 to 22, were charged on Friday with offences including affray, assaulting police and resisting arrest. Acting assistant commissioner Wayne Cox of the North West Regional Command said the two groups were of Pacific Islander background, with one originating from the Mt Druitt area and the other from around Granville.
He said police had been tipped off by members of the public and monitored Facebook and other social networking sites.
"Those particular sites are not for violence or to bring out mob mentality," Mr Cox told reporters on Friday. "And they should be used for social networking, as they are designed for." Facebook had provided police with some assistance, he added.
Police are reviewing CCTV footage from the centre and say they expect to make more arrests. A 16-year-old boy was due to appear in Parramatta Children's Court on Friday while three of the other males, aged 19 to 20, were due to face Mount Druitt Local Court on Friday.
The others are expected to appear at the same courts on February 24 and 25.