How the French police got their men - and women. After embarrassing close calls, tips brought success

At first, the police tried to infiltrate Direct Action, France's most notorious terrorist group. Impossible. The group numbers only a dozen or so activists. Newcomers are not welcome.

Yet the police succeeded in netting four of the group's leaders in a raid last weekend. And they did it through traditional police methods, tracking down sources, checking tips.

Initially, the police encountered a series of embarrassing close calls. In February 1984, Direct Action leaders Jean-Marc Rouillan and Nathalie Menigon were identified as suspects in a bank holdup, and traced to an apartment. But bad coordination among different agencies - one group arrives with its sirens blaring - allowed the two suspected terrorists to escape.

A month later, Mr. Rouillan and Ms. Menigon were traced to Brussels and identified while renting a car. But police confused an employee of the rental agency for Rouillan. The couple escaped. The trail turned cold. For the next two years, there were few new leads. When the law-and-order minded government of conservative Prime Minister Jacques Chirac came to power in the spring of 1986, it overhauled the country's antiterrorist forces and put a new emphasis on police coordination.

When the big break came last week, the police were ready. An informer identified Rouillan and Menigon from wanted posters in a village outside of Orleans and said they were living at a remote farmhouse.

Members of RAID, a 300-man special police antiterrorist group, put the farmhouse under surveillance. A computer was installed in a nearby farmhouse to insure direct communications with Paris headquarters.

For 36 hours, the police waited. Last Saturday evening, two other Direct Action leaders, Joelle Aubron and Georges Cipriani, arrived at the farm. The police moved in. Within minutes, the suspects were in handcuffs.

On Monday, the four Direct Action chiefs were transferred to a Paris prison. Police will interrogate them for the next few months. Sometime later, they will be tried for the murder of Georges Besse, president of the Renault auto company.

In a separate case, that of accused Lebanese terrorist Georges Ibrahim Abdallah - now being tried for complicity in the murders of two diplomats - police had to weave detective work with diplomacy.

On Aug. 6, 1984, at Villa Opicna on the Yugoslav-Italian border, a policeman was checking passports of passengers on train No. 260. He noticed a ``strange nervousness'' of a man with a Morrocan passport. He double-checked the man's baggage - and found 7.6 kilograms of Czechoslovak-made explosives. Police said the man, identified as El Mansouri, was a member of Mr. Abdallah's Lebanese Armed Revolutionary Faction.

Abdallah, living in Lyon, found out about his colleague's arrest. He believed the police or members of Israel's secret service, Mossad, were on his trail. On Oct. 24, 1984, he entered a local police station with an Algerian passport issued under a false name, saying he was an Arab militant whose life was in danger.

A routine check was ordered. Antiterrorist police at the DST, the French equivalent of the FBI, uncovered Abdallah's true identity. A policeman investigating Abdallah's bank account at the Geneva branch of Universal Bank discovered checks from the account had been used to pay for a Paris apartment. The police raided the apartment and found Abdallah's fingerprints, along with a Czechoslovak pistol, later confirmed as the weapon used in the murders of two diplomats.

But before the apartment raid, DST chief Yves Bonnet had struck a deal, through Algerian mediation, to free Abdallah in return for the release of a French diplomat kidnapped in Lebanon. The pistol find made Abdallah's early release impossible. Abdallah's followers retaliated with a bombing campaign in Paris last September.