Zimbabwean authorities have seized a U.S.-registered cargo plane carrying 64 "suspected mercenaries" and military equipment, the Home Affairs minister said Monday.

The Boeing 727-100 (search) was detained at Harare's main airport late Sunday after its owners allegedly made "a false declaration of its cargo and crew," Home Affairs Minister Kembo Mohadi said at a news briefing.

"The plane was actually carrying 64 suspected mercenaries of various nationalities," Mohadi said. "Further investigations also revealed that on board was military material."

It was not immediately clear where the plane had come from, or what its purpose was.

Mohadi gave no further information, but said full details would be released once officials have established "the true identities of the men and their ultimate mission."

State-run TV broadcast footage of a white plane with the tail number N4610. Inside the aircraft, the station showed two satellite telephones, radios, blue backpacks, sleeping bags, hiking boots, an inflatable raft, paddles, bolt cutters and what appeared to be a can of Mace.

No weapons were shown, but the station said officials were still going through the cargo section.

Western journalists were not shown the plane, which Mohadi said had been moved to the nearby Manyame military airfield, and the government's claims could not be independently verified.

Passengers and crew, all of them "heavily built males" and most of them white, were also taken to the base, where a detention barracks is located, state television reported.

The plane is registered to Dodson Aviation Inc. (search) of Ottawa, Kan. However, company director Robert Dodson said it had sold the aircraft about a week ago to a "reputable" South African company, Logo Ltd. (search

"I think they were going to use it for charter flights," he said by telephone.

There was no reply at the Pretoria-based company.

U.S. Embassy officials said the Zimbabwean government had not raised the issue with them.

In Washington, State Department spokesman Richard Boucher said he was aware of the reports but added: "We have no indication this aircraft is connected to the U.S. government."

President Robert Mugabe has repeatedly accused the United States and Britain of plotting to overthrow his autocratic regime.

In 1999, three American missionaries were arrested at Harare International Airport (search) trying to board a homeward Swissair flight with a stockpile of more than 20 rifles and handguns in their baggage.

Accused of plotting to assassinate Mugabe, the three were jailed for eight months. They said the arms were for self-defense during three years of work among converts in war-torn Congo.

Zimbabwe faces its worst political and economic crisis since independence from Britain in 1980. The government's often-violent seizure of thousands of white-owned farms for redistribution to blacks has plunged the country into turmoil.