Here in the City of No Secrets, quite a few people spent quite a few weeks keeping a big one -- the where-abouts of the six Americans who escaped last weekend from the Canadian Embassy in Tehran.

The State Department knew about them, of course. So did the government in Ottawa and several officials of the Canadian Embassy here. So did Sen. Frank Church (D-Idaho). So did Graeme Bannerman, a Senate Foreign Relations Committee staff member.

Jean Pelletier, Washington correspondent of a Montreal daily, La Presse, knew the secret, and finally told it on Tuesday. The Washington bureau of NBC News knew it. Newsweek knew it. Doug Clark, the managing editor of the Coeur d'Alene (Idaho) Press had a pretty good idea, and several other news organizations say they had some whiff of it.

Nobody told. Not only that, but the governments of the United States and Canada mounted no great campaigns to persuade anyone not to tell. For the journalists who kept the secret, it was a voluntary decision.

In a journalistic community that has spent years beating its collective breast about the decision not to print the story of the Bay Pigs before-hand, the crisis in Iran has been remarkable for the spirit of self-imposed restraint it has brought.

Pelletier, 31, slight and soft-spoken, says he began "playing with the numbers" shortly after the hostages were taken on Nov. 4 -- a period when the official figure on how many hostages there was fluctuating -- and quickly figured out that some of the Americans in the Tehran embassy were unaccounted for.

A few weeks later, at a briefing floolowing the burning of the American embassy in Islamabad, Pakistan, Pelletier heard the State Department spokesman, Hodding Carter, mention that some of the Americans there had taken refuge in friendly embassies. It suddenly came to him that this is what those missing Americans in Tehran must have done, too.

Pelletier began calling around, and he finally found a source in the Canadian embassy who confirmed that the Americans were being hidden in Tehran by the Canadian government. He won't say anything about his source, except to insist that it wasn't his father, Ferald Pelletier, the Canadian ambassador to France. "Each time I would come up with something in my career," says the younger Pelletier in slightly broken English, "they say Oh, he got that from his father. It insults him and me."

On Dec. 7 the Canadian ambassador here, Peter Tow, called Pelletier and urged him to hold the story. Pelletier said he would. "We commend you for your attitude," said Tow.

A week later Pelletier and his wife, Dianne, a freelance writer, went up to Montreal where they met for several hours with two of his editors. He told them the story and said he was convinced that, as he says now, "There is no scoop which is worth the life of a human being."

One of the editiors, Jean Sisto, "kept saying, I'm fifty-one per cent for it and forty-nine percent against it,'" says Pellitier, "but it boils down to whether you want to write it because we can't force you.'" Pelletier said he didn't want to.

In the intervening weeks, he passed word to the embassy that he was holding the story, and told no one but his wife. Once, he says, in a discussion with some friends from the Canadian Broadcasting Corp., "it almost slipped out," but he held his tongue.

On Monday, after the closing of the Canadian embassy in Tehran and the escape of the Americans, Canadian External Affairs Minister Flora MacDonald said on television that she had received a call from her U.S. counterpart, Cyrus Vance, thanking the Canadians for their cooperation in Iran.

Claude Saint Laurent, assistant news manager of La Presse, was watching that in Monteal. "I must say, my heart stopped beating right there," he says. Certain that the news would now come out, Saint Laurent called Pelletier and told him to start writing.

The story ran in the second editions of Tuesday's paper. "It's the first international scoop La Presse ever had," says Pelletier.

Richard Valeriani, State Department reporter for NBC, says he knew about the Americans in the canadian embassy for "several weeks", having found out from a source. He told several of his editors, and they jointly decided to hold the story.

"It wasn't hard,"he says. "It's like, in 1940, would you have given the address of Anne Frank? If the government asks you in the name of security, the choice is easy." (The diary of Anne Frank chronicled the life of a Jewish girl hiding from the Nazis in Holland in World War II).

Newsweek came across the discrepancy in numbers that had alerted Pelletier while it was preparing a cover story on the hostages in December. Then one of the families of the Americans in the Canadian embassy told a Newsweek reporter where the missing six were.

"We went to State with it," says Maynard Parker, Newsweek's executive editor. "They said yes. We decided on our own not to run it. We felt there would be people's lives at stake."

At Time, the Washington bureau chief, Robert Ajemian, says the editors "knew there were six and we knew they were somewhere." They inquired, and got a "very strenuous" and, in the end, "very convincing" recommendation from the White 'house and the State Department that they not run the story.

Clark in Coeur d'Alene was perhaps the first reporter to know the secret On Nov. 9 he had a long interview with Marge Schatz of Post Falls, Idaho, whose son Henry was one of the six in the Canadian embassy. She said the State Department had told her Henry was hiding in the Swedish Embassy in Tehran.

"Then, as I was leaving," says Clark, "she mentioned the Canadian embassy in passing as well."

"As a writer," he says, "I wanted to go with it. But I'm the managing editor here, too, and I really could see the harm coming out of it, as opposed to the merit of my getting the byline. So I ran it with him in an 'undisclosed location.'"