NEW YORK (AP)  --  Six African immigrants were charged on Wednesday with smuggling ivory worth hundreds of thousands of dollars into the United States by disguising it as wooden musical instruments and carvings.

The defendants were awaiting arraignment in federal court on charges of violating U.S. laws designed to protect dwindling elephant populations by tightly restricting imports of ivory.

The black market in African ivory ``threatens the continued existence of an endangered species and will not be tolerated,'' U.S. Attorney Benton Campbell said in a statement.

The investigation began in January when customs agents discovered that a traveler arriving at John F. Kennedy International Airport on a flight from Paris was carrying 36 ivory carvings from Cameroon that had been coated in clay to make them look like wood. The man, as part of a plea deal, later told investigators he had been recruited as courier by the defendants.

In March, agents intercepted a cargo shipment addressed to one of the defendants that contained ``ivory tusks disguised as guitar-like instruments,'' court papers said. The shipment was valued at $165,800.

Prosecutors said that as part of subsequent sting operation, an undercover agent posing as an African art dealer met with one of the defendants in August at a Richmond, Va. motel and paid $1,000 for several pieces of ivory.

``Ivory is very, very, very hard,'' the defendant told the undercover, according to court papers. ``Find it, buy it, bring it in -- big problem.''

In a later transaction, the same defendant described having to pay bribes, saying, ``In Africa, at the border when they see ivory, you have to give them some money.''

The investigation found that many of the illegal shipments ended up at a storage facility in the Chelsea neighborhood of Manhattan used by African art dealers. The works ended up being sold at art shows and to collectors nationwide, prosecutors said.

If convicted, the defendants face up to 20 years in prison.

Inset photos: Juliet Papa