The Justice Department yesterday announced indictments of 115 people in Operation Pisces, a massive undercover drug investigation in which U.S. drug agents posed as money launderers for South American cocaine cartels.

During the three-year operation, the Drug Enforcement Administration said, 351 other individuals were arrested and 19,000 pounds of cocaine were seized, along with $49 million in cash and assets.

The investigation was described in a Los Angeles news conference by Attorney General Edwin Meese III, who called it the "largest and most successful undercover investigation in federal drug law enforcement history."

"The results are unprecedented," he said. Meese was accompanied by Attorney General Carlos Villalaz of Panama, who is assisting. DEA officials said Panama, using a new law intended to halt money laundering of drug profits, yesterday froze 54 accounts in 18 Panamanian banks where drug profits linked to Operation Pisces have been deposited.

"This is perhaps the most significant outcome of Operation Pisces," said one senior DEA official. "This marks the first time we will be able to get behind the Panamanian accounts of major drug traffickers. Quite simply, the government of Panama has determined it will no longer be in the money-laundering business and offer a safe haven for drug profits."

DEA officials said that undercover agents posed as money launderers operating out of storefront offices in Miami, Los Angeles and New York. The officials said agents laundered $116 million, which was sent to numbered accounts in Panama. The agents then financed the investigation with $4.3 million they received in commissions.

"In the cocaine business, cash is a problem . . . . It's bulky . . . you've got to count it, you've got to move it," said one DEA official. "We were discrete, we were on time, and we took care of the business that needed to be taken care of."

"The trust level among the traffickers was incredible," said one official. "Our undercover agents became, if not family, then the highest confidantes of the traffickers. They told our agents things we never thought they would about their dope, their money and their operations."

Three of the alleged kingpins, all Colombian, were arrested yesterday afternoon at Miami International Airport as they arrived for meetings with their "money launderers." They were identified as Jose Auli Lopez Chacon and Anibal Zapata, alleged cocaine traffickers, and Jacobo Wasserman, an alleged money launderer.

The DEA said that Lopez-Chacon, who has a sixth-grade education, was the leader of a top Colombian drug cartel. Agents said Lopez-Chacon asked the agents to purchase a helicopter for him to visit his cocaine operation in the Colombian jungles. Officials said the agents took $800,000 of Lopez-Chacon's money, bought the helicopter and had it fitted to meet DEA's needs. Then they had the helicopter seized before he had a chance to use it. DEA is now flying the helicopter, officials said.

"Operation Pisces says to traffickers the world over that drug assets are everywhere insecure," Meese said. "There will be no safe havens for drug money. We will find it, and we will take it."