PANAMA CITY, FEB. 7 -- In response to an indictment by two Florida grand juries on drug trafficking and racketeering charges, Panama's strongman, Gen. Manuel Antonio Noriega, is striking back with an investigation of his accusers amid signs of a new press crackdown.

In a letter published today in newspapers he controls, Noriega asked Panama's attorney general, Carlos Villalaz, to "open an investigation to determine the origin and those responsible for these slanderous accusations so that they can be brought to justice in conformity with the Panamanian penal code." Noriega also charged in the letter that U.S. Justice Department officials had "recklessly" accused him of "false offenses."

Noriega's demand for an investigation appeared to be aimed at two of his former close associates: Jose Blandon, who was Panama's consul general in New York until the general fired him recently, and Floyd Carlton, who once served as Noriega's personal pilot. Both have testified before a federal grand jury in Miami about Noriega's alleged involvement in money laundering and drug trafficking in association with a Colombian cocaine ring.

Noriega's move to mount his own investigation came a day after he accused the U.S. government of seeking to suppress his "progressive, nonaligned ideas." In an impromptu speech at a Chinese restaurant to leaders of the pro-Noriega Democratic Revolutionary Party Friday night, Noriega also asserted that U.S. attacks on him stemmed from an American desire to keep control of the Panama Canal and maintain the "strategic position" of the U.S. military's Southern Command here.

Under the 1977 Panama Canal treaties, the United States agreed to turn over control of the canal to Panama at the end of 1999. At that time, responsibility for defending the canal is to pass from the 10,000 U.S. troops currently stationed here to the 15,000-member Panama Defense Forces now commanded by Noriega. Washington has denied any intention to renege on the treaties.

In his speech Friday night, Noriega repeated allegations that John Poindexter, then head of the National Security Council, demanded during a December 1985 visit to Panama that Noriega turn his country into a "beachhead" against Nicaragua, withdraw from the Contadora Group of Latin American countries that was working on a Central American peace treaty and "depoliticize" the Panamanian military.

Noriega claimed that his troubles with the United States arose from his flat rejection of Poindexter's demands. U.S. officials have denied Noriega's version of his meeting with Poindexter, who was replaced in November 1986 as a result of the Iran-contra scandal.

{In an interview on CBS' "60 Minutes," aired Sunday, Noriega contended that Poindexter told him that the United States intended to invade Nicaragua. "They were going to invade Nicaragua, and the only reason they hadn't done it was because Panama was in the way," Noriega said.

{Capt. Moises Cortizo, a Noriega aide who was interviewed on the same program, said Poindexter wanted Panama to find a pretext for invading Nicaragua. "They wanted Panama forces to go in with American forces, but we'd go in first," Cortizo said. "Then we'd get the support from the American troops that would be taking part in the invasion."

{In the interview, Noriega also attempted to counter the drug charges against him by displaying dozens of letters of commendation from the U.S. Drug Enforcement Administration. Two of the letters, signed by agency Administrator John C. Lawn, commended Noriega for his "long-standing support" for DEA and for his "personal commitment" to a DEA operation that put "drug traffickers around the world . . . on notice that the proceeds and profits of their illegal ventures are not welcome in Panama."}

In another reaction to the indictments by grand juries in Miami and Tampa, Fla., the Panamanian government reportedly has recalled its ambassadors to Washington, the United Nations and the Organization of American States. According to the state-run Radio Nacional, the Panamanian Foreign Ministry yesterday summoned the three envoys to a meeting here to discuss Panama's diplomatic relations with the United States. Foreign Ministry spokesmen were not immediately available for comment.

As part of an apparent press crackdown connected with the airing of the anti-Noriega charges here, police today took over the offices of an opposition newspaper, El Siglo, which recently resumed publishing after a six-month closure. The newspaper was among several opposition or independent news media banned by the military in July in a previous crackdown.

Friday night, the Ministry of Government and Justice closed the radio station KW Continente after it broadcast a report from Washington about the indictment against Noriega. In ordering the closure, Government and Justice Minister Rodolfo Chiari De Leon charged that the station's recent broadcasts had "incited to violence and attacked the security of the state."