A teenage boy was allegedly slashed with a machete after ten people gatecrashed a house party in Sydney's east yesterday evening.
Emergency services were called to an address on Carnegie Street in Chifley about 8.25pm following reports of a brawl.
Police were told around ten people, two of whom were armed with machetes, approached a 16-year-old and an 18-year-old at the front of the house.
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One witness told 9News the uninvited guests were dressed in ski masks.
They allegedly fled the scene before officers arrived.
Police believe the incident was a targeted attack.
Paramedics treated the 16-year-old at the scene for laceration to his back and legs and he was taken to Royal Prince Alfred Hospital in a stable condition.
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A crime scene has been established and police have commenced an investigation into the incident.
Anyone with information is urged to contact police or Crime Stoppers on 1800 333 000.
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