Investigators declared yesterday that they have gutted a giant Colombian drug cartel with charges against 77 people and four businesses accused of smuggling more than $50 million worth of cocaine, heroin, and marijuana into America.

Nearly 50 people had been arrested by yesterday in New York, Canada, Puerto Rico, California, and Miami, said U.S. Attorney, David Kelley.

He said the two-year investigation put 20-year veterans of the drug trade out of business.

The New York City police commissioner, Raymond Kelly, said the investigation, Operation Mallorca, started in 2002 when a detective arrested a drug dealer in Miami and persuaded him to cooperate with the government by infiltrating nine drug rings in New York City.

Before long, he said, investigators were monitoring the transfer of large sums of cash on street corners in places like midtown Manhattan and Flatbush, Brooklyn, following a money trail that demonstrated the reach of a massive drug operation.

In dribs and drabs, authorities poked holes in the drug cartel’s operations.

In November 2003, more than 725 pounds of the organization’s cocaine was seized in New York. In June 2004, more than 20,000 pounds of marijuana was seized from a fishing vessel off the coast of Antigua on its way to the United States.That same month, more than 1,000 pounds of cocaine and heroin destined for America was seized in Puerto Rico.

By yesterday, $50 million worth of cocaine, heroin, and marijuana had been seized, and $7 million in narcotics revenues had been snatched by the government from bank accounts in New York, Puerto Rico, and Miami, Mr.Kelley said.

“The flow of drugs to our friends and children has been impeded and disrupted, and our banking system has been purged of millions of dollars stained with blood and poison,” Mr. Kelley told a news conference.

Mr. Kelley and others praised the infiltration of a highly secretive and sophisticated black market peso exchange favored by drug organizations to launder their illicit proceeds.