- Man who shot accountant was killed during Friday's shooting
- Five suspects are being questioned about their connections to the crime
The male suspects, who ranged in age from 16 to 24, were taken into custody at four locations in 6 a.m. raids that involved more than 200 officers, police said.
On Friday, a 58-year-old New South Wales police civilian worker was shot dead as he was leaving the NSW police headquarters near Sydney.
The victim, Curtis Cheng, had been working with the NSW Police Force for 17 years and was with the finance and business division, police said.
The gunman was killed by special constables who came out of the building.
The shooting took place around 4:30 p.m. outside the headquarters in Parramatta, a western suburb of Sydney.
The five people arrested Wednesday are being questioned about their connections to the shooting, police said.
NSW Police Commissioner Andrew Scipione said Friday the department is "an organization in mourning" as the investigation continues.
"These are early days and we are a long way from establishing a full picture. The gunman's exact motivations remain a mystery," Scipione said in a news release. "I can confirm we have identified the gunman as a 15-year-old. We understand he is of Iraqi Kurdish background, born in Iran."