A Rhodesian intelligence officer described him as a "nut case." U.S. officials have labeled him a "troublemaker" and a braggart." A fellow American mercenary condemned him as "the type who gives professional adventures a bad name."

None of it seems to bother David Bufkin, 37, the much-publicized former crop duster who now openly and often describes himself as an experiment mercenary who has had "jobs" involving Angola, Zaire, Rhodesia, Mexico, Canand and Cuba over the last 18 months.

His most recent exploit was recruitment campaign in California newspapers for 80 to 100 American mercenaries to help Zaire fight Kalangan rebels in Shaba province, an effort he said was supported by the Central Intelligence Agency.

CIA and Zaire officials vehemently denied the story.

Bufkin's latest cliam has led to new controversy about native of Kerman, Claif., a lanky figure always conspicuous in his Stetson hat and cowboy boots with a "Hell's Angels" Tattoo on his forearm.

For, while most people who have met him agree that he comes across a "dreamer" and "opportunist," in some cases there appears to be a small but curious element of truth to his stories.

On the Zaire recruitment, diplomats in Washington and Zaire said there were reports that President Mobutu Sese Seko had "explored" the possibility of using mercernaries to back up his poorly disciplined army before Morocco agreed to send in 1,500 troops.

Bufkin has ties with Zaire, where he was based last year during the Angolan civil war while working for the U.S. backed National Front for the liberation of Angola. A French mercenary, who also said he had discussed a possible contract with Mobutu representatives in Europe, said Bufkin's name was brought up during negotiations.

No one mentionaed CIA links with Bufkin, however.

Bufkin has also claimed that he was involved in breaking up a Cuban spy ring in Canada late last year. He said he was recruited as a Cuban agent, but then turned "double agent" for the CIA. During a "training session" in Montreal, he said, he discovered that a man named Rodrigues was among the Cuban spies working from offices in Montreal.

Within days, the Canadian goverment expelled five Cubans on charges of running a "spy school" at the same address in Montreal. They included two Cuban diplomats, one named Jesus Rodrigues Verdes, the consul-general. No one has ever verified Bufkin's exact role in the incident.

In December, Bufkin appeared in Rhodesia, again claiming that he was working as a double agent for the U.S. and Cuban governments. He said his assignment of Cuba was to make contact with Cuban agents and obtain military information on the four-year-old guerrilla war in Rhodesia. For the United States, he alleged, he was to "break the Cuban spy network in Rhodesia."

Bufkin added that he was being helped by Rhodesia's Special Branch intelligence organization, specifically a man named Bailey, who would pay his expenses, Bufkin claimed.

A tope Special Branch official said later that Bufkin's story was '80 per cent fantasy," adding, "We don't need a nut case like Bufkin to help us flush out intelligence agents."

But the manager at one of the three hotels where Bufkin stayed said he was introduced to the Californian by a man named Bailey, who gabe a telephone number corresponding to an unlisted Special Branch number.

The manager added that Bufkin checked out Dec. 17 without paying his bill. The next day Bailey returned to pay it. Rhodesian intelligence officials have since admitted that they did have an employee named Bailey.

Shortly before leaving Rhodesia, Bufkin said he had broken the spy nework of three key agents and was going to Botswana to track down two who had fled across the border because they realized they had been uncovered.

About the same time there were two widely publicized defections from the Rhodesian army by American and British "foreigh volunteers" although there was no evidence that the cases were connected with Bufkin.

In fact, Rhodesian officials said Bufkin left after their "invitation" that he do so. Informed sources say he is now banned from entering the troubled southern African territory.

Bufkin's reputation for exaggerating and talking too much has led many to question his llaged ties with three reporters in Rhodesia, two of whom, he had just met in bars, about his "assigment" in southern Africa.

Many of those who have worked with him have expressed their bitterness publicly, especially those involved in his Angolan operation.

Although Bufkin bragged loudly in the intercontinental Hotel bar in Kinshasa that he would bring more than 2,000 mercenaries to Angola, he ende d up with only six - two of whom were killed and three captured within three days of entering Angola. Among the four mercenaries executed after a military trial in Angola last year was a Bufkin recruit, Daniel Gearhart of Kensington, Md.

One who escaped said later in an interview with Soldier of Fortune magazine that Bufkin had misled his recruits about their role and lied about the military supplies available to them.

A question that remains is why Bufkin has never been prosecuted for recruiting mercernaries for a foreign army. Both recruiting mercenaries and leaving the United States to serve as one are illegal under the U.S. Neutrality Act. It provides for fines of up to $1,000 or three years in jail or both for any person convicted of leaving the country with the intent of fighting for pay, "in the service of any foreign prince, state, colony, district or people."

The Long Island newspaper Newsday reported last month that the CIA had quietly passed word to the U.S. Justice Department that it would not cooperate in a pending investigation of Bufkin's activities. CIA spokesman Herbert hetu denied the report.

(Former CIA employee John Stockwell wrote in The Washington Post on April 10 that a colleague of his had "purged" the CIA's records on Bufkin last fall in anticipation of the possibility that Bufkin might seek access to them under the Freedom of Information Act if he were put on trial. Stockwell wrote that Bufkin had "apparently" received money from FNLA leader Holden Roberto, quite possibly from funds he received from the CIA.")

Another question about Bufkin's possible CIA links surfaced when it was discovered that one of his six recruits for the Angolan war was George Bacon, a highly decorated CIA agent with service in Laos. Bacon was killed shortly after entering Angola.

Bufkin has even given the name of his alleged CIA liaison agent, a Col. Harvey in San Francisco.

The CIA continues to deny any involvement with Bufkin, claiming he falsely uses the CIA's name as a means of trying to legitimize his operation.