The Interior Ministry said that the contractors, two Britons, who were detained on Tuesday after being found with an arsenal of unlicensed AK-47 assault rifles in their sport utility vehicle, were among the 341 Afghan guards and 35 foreign contractors employed by GardaWorld in Afghanistan.

At a news conference in Kabul, the authorities put on display the two Britons as well two Afghans who were detained — their driver and their interpreter. Seddiq Seddiqi, an Interior Ministry spokesman, said the rifles had been found wrapped in blankets inside a metal box in the trunk of the vehicle. The rifles, which the government said had their serial numbers scratched off, were also shown to reporters at the news conference.

GardaWorld, in a statement, said that it did not yet own the weapons and that its guards were taking them to a rifle range for testing. “The weapons in question were being taken to be tested at a firing range before being purchased and properly licensed by GardaWorld,” the company said, adding that in its discussions with the government it hoped to clear up what it implied was a misunderstanding and “rectify the situation as soon as possible.”

The company said it had complied with all Afghan laws and regulations in its operations in the country, where it provides mobile escort guard services and protection for compounds and bases. It would not specify which compounds or bases it protected.

The Interior Ministry said that the company had contracts to work in Kabul, Herat, Kandahar and two other cities, and that GardaWorld was one of 46 security companies licensed to operate in Afghanistan until March 2012.