On June 24, outside a Westfield shopping center on Carlisle Avenue in Mount Druitt, an alleged stabbing incident involved two men, aged 17 and 22.
The 22-year-old was allegedly stabbed in his back and suffered a punctured lung, while the 17-year-old sustained slash wounds to his arm. 
Police arrested and charged two men following the incident, aged 18 and 20. They remain before the courts.
Following investigations, an 18-year-old man was arrested at a home on Gordonia Grove in Baulkham Hills at 10.30pm last night.
The teenager was brought to The Hills Police Station and faced charges of wounding someone with the intent to cause serious harm, along with robbery in company.
The 18-year-old man was refused bail and will appear in Parramatta Local Court today.
Following the alleged attack, police said the incident started when a verbal altercation erupted between a group of men.
The group separated, but came across each other again 15 minutes later in the car park outside Kmart in Westfield Mount Druitt, opposite Dawson Mall.
A physical altercation broke out, the 22-year-old man was allegedly stabbed. He ran inside the Kmart for help from staff.
Both men survived the attack. 
