Metropolitan Superintendent Anthony Wagambie Jr said the two men were dressed in police uniforms with a fake search warrant held up the shop owned by Indians and stole over K15,000 in cash.
The two men were apprehended at West Taraka in Lae following a drinking spree two days later.
Wagambie said the Police Intelligence Unit managed to track the suspects apprehending 15 suspects with the two charged.
They had escaped in a Land Cruiser to Lae where police were tipped off and detained the two men.