Police are pleading with a woman who took her six-year-old son from Canberra without permission to come forward and prove he’s ok.

Police have grave concerns for the safety of Phoenix Mapham, who was last seen on Thursday with a woman believed to be his mother, Tessa Woodcock.

They were last seen in a white 1999 Holden Vectra sedan (ACT rego YAU56P) near the ACT suburb of Weston Creek.

However, police say they might also be travelling in a blue Subaru Forester with a broken rear window and damaged front end (rego YKP08U).

Please re-tweet! Police are still looking for missing six-year-old boy Phoenix Mapham. Phoenix was last seen in a white 1999 Holden Vectra sedan (rego YAU56P) leaving Hickey Court, Weston Creek about 1.30pm Thurs 23 Aug 2018. More here: https://t.co/rGGCnokCQC #AmberAlert pic.twitter.com/YmUScwefCB

— ACT Policing (@ACTPolicing) August 28, 2018

ACT police Detective Station Sergeant Harry Hains has told Ben Fordham that “amber alerts are not issued lightly and this is the first one issued in the ACT”.

“If Tessa is listening… we need to know that your son is ok we need to see him.

“We’re talking about his health and his safety… you need to bring him to a place where we can verify that you are taking care of him”.

Police are asking anyone with information to phone the Police Assistance Line on 131 444 or ACT police on (02) 6256 7777 and quote reference number 6300755.

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Photo: ACT Police