BERLIN - While a legal battle is still underway in Israel over the fate of Franz Kafka's manuscripts in Tel Aviv, two documents in the noted author's own hand were auctioned off Thursday in Basel, Switzerland.

As is customary on such transactions, the identity of both the seller and the buyer is confidential. However Haaretz has learned that, as in previous cases, these documents had at one point been held in Israel by Esther Hoffe. Hoffe inherited Kafka's estate from the essayist Max Brod, whose secretary she had been.

The National Library in Jerusalem tried to block the sale, but the auction houses involved did not offer any cooperation.

One of the documents sold Thursday is an eight-page letter written in September 1922, two years before Kafka's death, from the author to Brod - who was his closest friend and literary executor. In cramped handwriting, Kafka wrote: "I know allusions of the terror of loneliness. Not so much the loneliness of being alone, as that among people."

The German publisher Klaus Wagenbach, who was very close to Brod and is considered the world's foremost authority on Kafka, called the letter "one of Kafka's most beautiful ever." Esther Hoffe sold this letter about 30 years ago to a private individual, who sold it Thursday in Basel for 125,000 Swiss francs (approximately NIS 472,000).

Also auctioned Thursday in Basel was an envelope in Kafka's handwriting, dated February 7, 1913. It was addressed by Kafka in Prague to Felice Bauer, who lived in Berlin. Bauer, one of the few women with whom Kafka was romantically involved, had a great influence on his writing. They met in 1912 at Brod's home, were engaged twice, and broke up finally in 1917. The five years of their relationship are considered Kafka's most prolific time period. One of his best known works, "The Verdict," he wrote in one night, around the time he met Bauer, and dedicated it to her. Among other well-known works written at this time are "The Metamorphosis" and "The Trial."

The envelope, sold Thursday for 3,600 Swiss francs, had contained one of the hundred of letters the couple sent to each other over the years; these letters are an important literary work in their own right, revealing Kafka's tortured love life.

After separating from Kafka, Bauer married and subsequently bore two children. She died in New York in 1960.

Before the auction Thursday, attorney Meir Heller, whose firm represents the National Library in Jerusalem, wrote to the two auction houses that had organized the sale in an attempt to stop it. The auction houses were told that the sale should not go forward, as the issue of who the manuscripts belong to is still being decided in the Israeli courts. In the 40 years since Brod's death, the documents have been kept in bank vaults and in the Tel Aviv apartment belonging to Hoffe.

Heller wrote that, to the best of his knowledge, one of the two items sold Thursday (the letter from Kafka to Brod), is part of the Brod estate, which is still in dispute. He also wrote that the Israeli court had appointed an executor and according to Israeli law, the sale of any item from the estate had to be approved by the court, therefore Heller asked them to reconsider the auction. However the two auctions houses, Moirandat from Switzerland and Stargardt from Germany, ignored his request.