Britain Lifts Curtain on Security Agency : Government: MI5 breaks precedent with photograph of director in her office, brochure detailing its activities.

Britain’s internal Security Service came out of the shadows Friday in a dramatic public unveiling of an agency that until recently denied its very cloak-and-dagger existence.

The 80-year-old Security Service, known as MI5, published a booklet detailing its activities and allowed the director general, Stella Rimington, to be photographed in her heretofore top-secret office.

It was the first time a director general had made a public engagement since MI5 was founded in 1909.

The glossy brochure gave details of the Security Service’s organization and activities that the Soviet KGB and other intelligence agencies spent years and millions of dollars trying to obtain.

Encouraged by Prime Minister John Major to be more open, the Security Service published a post office box in London where members of the public who want to contact MI5 can offer information.

The 36-page brochure, obtainable at the Government Stationery Office for $7.50, displays for the first time MI5’s own badge, a heraldic beast over the motto Regnum Defende, which means Defend the Realm.

The document also gives a breakdown of the agency’s resources, though not an overall budget total.

Britain’s war against terrorism--including the activities of the Irish Republican Army--accounts for 70% of the Security Service effort. Twenty-five percent is devoted to counterespionage and counterproliferation--the latter against the growing threat from “weapons of mass destruction . . . nuclear, chemical and biological.”

The remaining 5% is for fighting subversion, which is now seen as a much-diminished threat.

The brochure notes that MI5 employs about 2,000 people, half of them women. The elite consists of just under 340 men and women, members of the General Intelligence Group, which carries out surveillance, phone taps, interception of mail and “entry into, or interference with, property.”

The report adds that “agents working within a target organization, or reporting on individuals under investigation, represent the other most significance source of secret intelligence.”

Their work “involves the identification, recruitment and subsequent careful direction of an individual within, for example, a terrorist group or a hostile intelligence service.”

Although the threat from subversion “is now very low” following the end of the Cold War, MI5 continues, the brochure says, to monitor “the possibility of extreme right-wing, nationalist and racist groups on the Continent, establishing contact with sympathizers in this country.”

The Security Services were established originally to counter the danger of German espionage. They were soon separated into domestic and foreign operations that became known as Military Intelligence-5, or MI5, and Military Intelligence-6, which later was called the Secret Intelligence Service, or MI6.

MI5 comes under the supervision of the Home Office, while MI6 is under the direction of the Foreign Office.

Rimington, 58, was appointed director general last year after a career in the service including undercover work. She was first ever to be named officially.

Since then the Security Service has taken over the major coordinating and investigating role in seeking out IRA and Ulster unionist terrorists.

And she has presided over the move of MI5 from several London offices to new headquarters along the Thames River, across from their sometime rivals, MI6.

While opening up MI5 to public scrutiny, Rimington (known as Mrs. R inside the agency) defended her service against “fanciful allegations surrounding its work,” which have included suggestions that the agency bugs the Royal Family.

“It is difficult,” she said, “to comment on allegations about the service without revealing, by what is said or not said, information that might compromise past, present and future operations.”