THE headline was irresistible. "Dangerous Liaison" it said, and underneath was a picture of "top IRA man" Gerry Kelly and Martha Pope, chief aide of ex Senator George Mitchell, who is chairing the North's multi party talks.

The Mail on Sunday said MI5 had discovered that the pair had been meeting secretly. The story stunned Northern Ireland.

It had all the necessary ingredients: a hardline republican with film star good looks and an attractive, sophisticated US diplomat who, the Mail informed us, was "charming but ruthless". Mr Kelly was said to have written romantic poetry to his "lover".

The same story appeared simultaneously in the Sunday World, owned by Independent Newspapers. But once it was subjected to even the most superficial examination and checking, there were many things which did not ring true.

Firstly, Mr Kelly, Ms Pope and everyone who knew them totally rejected it.

"Absolute rubbish," said Mr Kelly.

"Completely without foundation," said Ms Pope.

"Scurrilous and totally false," said Mr Mitchell.

Would they risk their reputations by issuing such categorical denials if MI5 possessed contrary evidence?

The quality newspapers smelt a rat and did not give the story credence. But the tabloids continued to rake over the claims. While carrying the widespread denials, the Express of London said Ms Pope's lips were "eminently kissable" and described her wrinkling her "perfectly shaped nose".

As the week unfolded the story died. But the damage had already been done. Ms Pope's standing was compromised.

So where did the story originate? The most popular theory among journalists is that the DUP heard vague rumours and, asked the British government to investigate. The party was then able to tell reporters at its" annual conference last weekend that MI5 was inquiring into an alleged relationship between a republican and a US aide.

It seems likely that whoever initiated the story wanted to damage the peace process.

The Progressive Unionist leader, David Ervine, said it was an attempt to end multi party talks. The SDLP accused MI5 of dirty tricks.

But the smear on Ms Pope and Mr Kelly is not a new departure in Northern Ireland. It is just the latest in a long line of similar incidents throughout the troubles.

A British army manual in the 1970s referred to "psyops", psychological operations against the enemy, carried out in support of British political and military interests.

In the 1970s a British army press officer circulated a document which he claimed was the Sinn Fein oath. It was later proved to be a forgery.

Journalist David McKittrick recalls how tabloid reporters would ring up Mr Colin Wallace, a British army press officer in the 1970s, to get the names, addresses and telephone numbers of the "mistresses" of loyalist and republican paramilitaries.

In 1974 the Sunday Times reported that a committee made up of Northern Ireland Office, British army and RUC representatives met at Stormont Castle to discuss ways of "discrediting politicians judged hostile to government policy".

Republican leaders relish concentrating on British dirty tricks, but they are far from lily white themselves. They do not want reporters to have independent republican contacts at grassroots level.

The IRA's so called GHQ department has circulated rumours about journalists with such contacts, alleging that they are MI5 agents. Such efforts are aimed at sowing distrust of these reporters among republican grassroots.

The IRA is also known to have tapped the telephones of journalists in Northern Ireland.

Black propaganda is regarded by many protagonists in the conflict as just another tool of war. Moral scruples are unlikely to stand in their way.