Homeowners in Downer were threatened at gunpoint by a masked man during two separate aggravated robberies that police believe are linked.
Police say the man broke into a home on Melba Street in the inner north suburb about 5.10am on Sunday.
The intruder then demanded the resident's car keys, but the offender left the scene empty handed.
An ACT police spokesman said two vehicles at the Melba Street address were ransacked.
Just 30 minutes later, the man was reported to have broken into a home in nearby Atherton Street , where he also threatened a resident with a gun, demanding car keys.
The resident gave the keys to a white Volkswagen Polo to the offender, before the offender drove away.
Police say the Polo has since been recovered by officers.
The man has been described by police as Caucasian, tall and having blue eyes.
He was seen wearing dark clothing at the time of the incidents, a black cap and a red bandana across his face.
Police say the man was accompanied by a woman during the break ins, who has been described as "very short" and wearing a bulky black jacket.
Police are urging anyone with dash cam or security footage to come forward to CrimeStoppers on 1800 333 000.