A secretive encounter with a Bedouin robber in a desert valley has led to what one Israeli archaeologist hailed as one of the most important biblical finds from the region in half a century.

Professor Chanan Eshel, an archaeologist from Tel Aviv's Bar Ilan University, said the discovery of two fragments of nearly 2,000 year-old parchment scroll from the Dead Sea area gave hope to biblical and archaeological scholars that the Judean Desert could yet yield further treasure.

"No more scrolls have been found in the Judean Desert since 1965. This encourages scholars to believe that if they bother to excavate, survey and climb they will still find things in the Judean desert. The common knowledge has been that there is nothing left to find there," Eshel said.

The two small pieces of brown animal skin, inscribed in Hebrew with verses from the Book of Leviticus, are said by Eshel to be from "refugee" caves in Nachal Arugot, a canyon near the Dead Sea, where Jews hid from the Romans in the second century.

Amir Ganor, head of the Authority's archaeological theft unit, declined comment.

Recently, several relics bearing inscriptions, including a burial box purported to belong to Jesus' brother James, were revealed as modern forgeries.

Archaeologist and Bible scholar Steven Pfann said he had not seen the fragments.

If authenticated, they would "in general not be doing more than confirming the character of the material that we have from the southern part of the Judean wilderness up until today."

But, he added, "what's interesting and exciting is that this is a new discovery...this is the first time we've seen anything from the south since the 1960s."

Eshel said he was first shown the fragments last year during a meeting in an abandoned police station near the Dead Sea.

A Bedouin who had been offered $US20,000 ($A26,660) for the fragments on the black market wanted an evaluation, an encounter that both excited and dismayed the archaeologist who has worked in the Judean Desert since 1986.

"I was jealous he had found it, not me. I was also very excited. I didn't believe I would see them again," said Eshel, who took photographs of the pieces he believed would shortly be smuggled out of the country.

But in March 2005, he discovered the Bedouin still had the pieces of scroll. Eshel said he bought them with $US3,000 ($A4,000) provided by Tel Aviv's Bar Ilan University and subsequently handed them over to the Antiquities Authority.

"Scholars do not buy antiquities. I did it because i could not see it fall apart," Eshel said

Eshel said that the fragments constitute the 15th scroll found in the area from the same period of the Jewish "Bar Kochba" revolt against the Romans, and the first to be discovered with verses from Leviticus.

More than 1,000 ancient texts - known collectively as the Dead Sea Scrolls - were discovered between 1947 and 1956 in 11 caves overlooking the western shores of the Dead Sea.