A 79-year-old preacher in the southern U.S. state of Mississippi, known as a longtime member of the white supremacist Ku Klux Klan, has been put on trial for the notorious murder in 1964 of three civil-rights workers.

The defendant, Edgar Killen, is accused of recruiting a gang of men who carried out the killings, an event that galvanized national attention and gained sympathy for civil-rights campaigners in the American south nearly half a century ago.

The victims -- three young men, two white and one black -- had been working on a campaign to help black Americans gain the right to vote.

Mr. Killen, a part-time preacher who also operates a lumber mill (in the town of Philadelphia, Mississippi), pleaded not guilty to all charges as his trial began Friday. He is being held without bail.

------

Until now, the state of Mississippi had never tried anyone in connection with the 1964 murders. Three years later, federal authorities charged Mr. Killen and 17 other men with violating the civil rights of the murder victims. Seven defendants were convicted, but an all-white jury was unable to agree on a verdict against the 11 others (including Mr. Killen).

One of the jurors reportedly said at the time that she was unable to convict Mr. Killen because he was a preacher.