Three armed men forced their way into a Hackett home, threatened a woman holding a child at knifepoint and stole cash and a Mercedes-Benz sedan.

Police said the men, armed with a firearm, knife, sword and baseball bat, entered the Harris Place home about 11pm on October 5.

The men allegedly threatened the woman with a knife while demanding money.

One of the men allegedly struck the woman in the head before the group stole cash and the car.

The child was unharmed.

Police described the three men as Polynesian in appearance, wearing black balaclavas and black clothing.

Anyone who witnessed suspicious activity in Hackett on October 5 or has information about the home invasion should contact police via the Crime Stoppers ACT website.

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