The ghost of St-Germain

In 1965, Mehdi Ben Barka, iconic African politician, was stopped in a fashionable Paris street by two gendarmes; he was never seen again, and for 36 years his fate was a mystery. Now the truth has emerged. John Lichfield recounts a shameful tale of kidnap, torture and assassination

Just after 12.15pm on Friday 29 October 1965, a slight, balding man stood outside the Brasserie Lipp, one of the fashionable cafés on the Boulevard St-Germain on the Left Bank of Paris. De Gaulle was still President of the Republic; Wilson was in Downing Street; and Lyndon Johnson was in the White House. Sartre and De Beauvoir were, in all likelihood, holding court at the Café de Flore across the road.

Two policemen, belonging to the Paris vice squad, drove up and arrested the man, who was waiting outside the Lipp to meet a film director and a journalist. His family and friends never saw him again.

His disappearance became, briefly, a political scandal in France. It shook, but did not unduly threaten, Le Général's domination of French politics. The man became a kind of Gallic Jimmy Hoffa or Lord Lucan (although more deserving than both). Others have compared him to Che Guevara, even to Mandela. But while he was undoubtedly a hero in radical circles before his disappearance, his defining attribute ever since has been the mystery surrounding his fate.

Even in recent years, rumours have surfaced that his body remains buried in northern Burgundy; underneath a mosque in the south-Paris suburbs; or on the Ile de la Grande Jatte, an island beloved of the post-Impressionists on the Seine, west of Paris.

His name was Mehdi Ben Barka. He was 45 years old. He was a socialist, exiled Moroccan opposition leader. Depending on your political perspective, he was a political saint or a troublemaker. He was one of the "lost" leaders of the post-colonial world, a man who could have created the pattern for a different, more democratic kind of Third World politics. Alternatively, he was a dangerous enemy of the West, in the pay of Moscow and Havana. A French politician once described him as a "commercial traveller in revolution".

In the past few days, the French newspaper Le Monde and the Moroccan newspaper Le Journal have published the results of a long investigation that appears, finally, to resolve the mystery of what happened to Mehdi Ben Barka.

He was, as has always been suspected, kidnapped by the Moroccan authorities, on the orders of the late King Hassan II. (Ben Barka had once been the monarch's mathematics teacher and, briefly, his political mentor, but the two had quarrelled violently since Hassan became king in 1961.)

Ben Barka was, according to the account of the two newspapers, taken to a château south of Paris, and tortured by the Moroccan interior minister in person. The intention had been to bring him back to Morocco and murder him there, to avoid embarrassing the French former colonial power. But the torture got out of hand, according to the account given to the newspapers by a former Moroccan security agent. Mehdi Ben Barka died, it is reported, after the skin of his chest had been repeatedly slashed with a stiletto in a drunken rage by Mohammed Oufkir, the Moroccan interior minister. His body was then smuggled back to Morocco via Orly airport, with the connivance of the French authorities.

There, his remains were dissolved in a giant vat of acid, which had been purpose-built to get rid of dead opposition leaders by the Moroccan security services. The plans and technical specifications for the vat were allegedly provided by the CIA.

The entire operation to kidnap Ben Barka was undertaken with CIA approval, the two newspapers said. The French authorities may not have known about it beforehand, but they certainly conspired with the Moroccans – in the name of good post-colonial relations and to prevent Morocco from falling wholly under US influence – to allow Ben Barka's body to be smuggled back to Rabat and oblivion.

On the whole, this is a convincing account, and squares with the known facts, including those that emerged at the two trials of some of the figures involved in the affair in 1966 and 1967. The first trial's results were quashed – and although there were several convictions in the second, including, in his absence, a conviction for murder for Mohammed Oufkir, many questions have always remained unanswered.

The weakness in the two papers' new account is the relatively lowly stature of their main informant. Ahmed Boukhari, 62, was, in October 1965, in charge of the switchboard at the Moroccan security service, known as "Cab 1". He took immaculate notes of the messages that passed to and fro between HQ and the Moroccan agents, and senior officials, in Paris.

He has handed these notes in full to the newspapers and says that he is prepared to answer questions from the French investigating judge still trying to get to the bottom of the affair. His notes include, for instance, a message to Rabat from Mohamed Achaachi, head of Moroccan counter-subversion, on the day of Ben Barka's kidnapping. The message reads: "Mission accomplished. The package is ready for dispatch. Send the plane."

Much of the rest of the newspapers' account, however, comes from unnamed sources and hearsay within the security services recalled by Mr Boukhari, now retired and still living in Morocco. There are no corroborating sources of evidence for the acid-vat story, nor for the connivance of French authorities in the shipping home of Ben Barka's body (although some sort of connivance is likely). "I decided to speak so that the Moroccan people – starting with Ben Barka's family – could find out what really happened," he said.

Controversy will continue to swirl around the affair. The whole truth cannot emerge until the Moroccan, French and American authorities agree to reveal what they, officially, know, which is not likely to be soon. Last month, the Moroccan authorities allowed a French investigating judge, leading the continuing Ben Barka inquiry, to visit Rabat for the first time. He was politely received but given no information. French documents on the affair are still partly declared to be "defence secrets". The CIA is believed to have 3,000 sheets of paper on the disappearance of Ben Barka. Despite the 1976 Freedom of Information Act, the CIA has repeatedly refused to declassify any of these documents.

Mehdi Ben Barka – nicknamed The Dynamo – was born to a relatively poor family in Rabat in 1920. He became a brilliant mathematician, and, from the age of 16, one of the leaders of the movement for Moroccan independence from France.

Initially, he supported the restoration of the monarchy, in the shape of Hassan II's father, Mohammed V, when Morocco became independent in 1956. Indeed, when Hassan II came to the throne, five years later, he spoke of including Ben Barka as a "balancing force" in his government. But the former teacher and student quarrelled over Hassan's autocratic and brutal regime. Ben Barka lived, increasingly, abroad and was permanently exiled in 1963 after being condemned to death, in his absence, for undermining state security.

Even up to the month before his murder, Hassan II, who liked to play at being an enlightened monarch, spoke of inviting Ben Barka into his government. Privately, however, the king and his ministers blamed the exile for fomenting riots against the monarchy. By this time, Ben Barka had become a star of the international, anti-imperial and anti-colonial Left, jetting between Moscow and Havana, and living, mainly, in Switzerland.

According to Le Monde's account, his kidnapping and assassination was ordered by King Hassan on 25 March 1965, after especially bloody riots in Casablanca had caused hundreds of deaths. Over the next seven months, the exile's movements were closely tracked. The next part of the story has been well-documented over many years. A French journalist and film director were bribed to approach him for help with a movie about the end of colonialism. Ben Barka was waiting to meet them outside the Brasserie Lipp when two French policemen – also bribed by the Moroccan security services – drove up and arrested him.

Le Monde and Le Journal believe that they have now lifted the veil on what happened next. They say that he was taken to a château at Fontenay-le-Vicomte, south of Paris, and treated well at first. It was only when the interior minister, Mohammed Oufkir, arrived late that night that Ben Barka was tortured and finally – accidentally, it is alleged – murdered.

Oufkir was later sentenced to life for his part in the affair by a French court. He was never given up by the Moroccan authorities but was himself murdered – by King Hassan in person, according to one account – after leading a coup d'état in 1972.

The two bribed French policemen served short prison sentences. Three French minor criminals hired to help the Moroccans were allowed, mysteriously, to flee to Morocco, where they lived under the protection of the Moroccan security services before disappearing, equally mysteriously, in the mid-1970s. They are believed to have been murdered.

The one question that will never be resolved is the true nature of the politics of Mehdi Ben Barka himself. Was he a different, more democratic kind of Third World politician – a Moroccan Mandela – as his admirers claim? Or would he have proved to be just as venal and autocratic as many other of the 1960s generation of idealistic, post-colonial leaders?

The fact that we shall never know is both a tragedy and a shameful reflection on the "First World" regimes of 1960s France and America.