The Assistant Deputy Commissioner of Customs and Trade in Tonga says it needs better equipment to counter the illegal importation of weapons.
This comes after a recent charge of unlawful possession of a firearm, laid against man alleged to have shot a security guard outside a nightclub.
Kelemeti Vahe from the Customs and Trade division says it is carrying out more inspections of shipping containers, searching for illegal guns and ammunition.
But he says bigger x-ray machines are needed to scan large shipping containers.
"We do things here manually, meaning we take everything out by staff taking everything out, opening up, checking it and then putting everything back again. We do have an x-ray with the assistance of one x-ray truck but only for small sized items."
Kelemeti Vahe says a sufficient sized x-ray machine would cost up to three million US dollars.