A 13-year-old and a 14-year-old have been charged with aggravated robbery but three other young alleged offenders have not been identified following an alleged assault at a service station in Eaton on Tuesday, NT Police said.

In a statement NT government crime marketing manager Sita Bacher said that about 4am five youths allegedly stole a vehicle after threatening and assaulting a man at the Ampol service station on Osgood Drive.

She said one of the youths was allegedly carrying a machete during the assault and the victim sustained minor injuries. It was not made clear if the attendant was attacked with the machete.

The 13-year-old and the 14-year-old were each charged with aggravated robbery, and use of a vehicle without consent and theft, and they were bailed to appear in court on July 24, Ms Bacher said.

Police have not identified the other three alleged offenders. Police are looking for witnesses to call 131 444.