MADRID, Spain - A Spanish historical archive has found what may constitute the largest collection of ancient Hebrew manuscripts in Europe on discovering fragments of medieval texts stuffed inside the covers of books.

"It's too early to say just yet as we're not sure how many there are but it could be the most important in Europe," said Josep Matas, director of the Provincial Historic Archive of the northeastern town of Girona where the documents were found.

Girona was one of the most important Jewish population centers in Spain prior to the expulsion of all non-Catholics in 1492 by the Catholic kings Isabel and Ferdinand. Matas believes the town once had some 700 Jews.

Matas said the first manuscript fragment was found several years ago but archive personnel thought it was a one-off discovery.

He said recent investigations unveiled up to a thousand document fragments hidden in the covers of books and the archive believes there could be many more.

"Back in medieval times, book covers were made firm by padding, or filling them with other documents thought to be of no value," Matas told The Associated Press by telephone Wednesday.

He said that so far they had found fragments in 165 tomes. The books, mostly Girona provincial notarial works, are important in themselves but the material in their covers could be of much greater historical value, he added.

Matas said the fragments studied and restored so far included texts from the Book of Genesis and the Torah as well as marriage and business contracts.

The Hebrew documents are most likely remnants of what Jewish families left behind them when they fled. He said many Hebrew documents from the city had been destroyed in an anti-Semitic attack in 1391. Jewish families that fled a hundred years later also took much documentation with them.

The archive has restored the fragments found in five books and plans to leave the rest in the book covers.

"Most of the pieces are glued into the inside of the covers and we have to ascertain what type of glue it is in each case before we can extract them," said Matas.

The archive is currently looking for financial support to recuperate all the texts. It plans to stage an exposition detailing the discovery in October.