The 12-year-old will be dealt with under the provisions of the Youth Justice Act 2005.
The 14-year-old is expected to be charged with Use motor vehicle without consent.
The 20-year-old is expected to be charged with four counts Aggravated robbery, five counts Aggravated burglary and one count Use motor vehicle without consent.
Detective Superintendent Drew Slape said, “Northern Territory Police will continue to work tirelessly to investigate this type of appalling offending and place those responsible before the courts.
“Investigations into these incidents are ongoing and detectives with the Alice Springs Criminal Investigation Branch urge anyone with information to contact police on 131 444”.
Anonymous reports can also be made through Crime Stoppers on 1800 333 000 or via https://crimestoppersnt.com.au/.
