PARIS — For more than two decades, 250 historians and specialists labored to produce the first six volumes of the General History of Latin America, an exhaustive work financed by UNESCO, the United Nations organization created to preserve global culture and heritage.

Then, over the course of two years, UNESCO paid to destroy many of those books and nearly 100,000 others by turning them to pulp, according to an external audit.

"This is the intellectual organization of the United Nations system," Aziza Bennani, Morocco's ambassador to UNESCO, said in an interview. "How could an employee of UNESCO make a decision to destroy these books?"

Homero Aridjis, Mexico's ambassador, said at the organization's executive council meeting this past week, "This is not only a blow to the culture and knowledge of entire populations and nations, it contradicts the mandate entrusted to UNESCO." He demanded an internal investigation.

UNESCO Director General Koichiro Matsuura said it was "completely incomprehensible and inappropriate" that some of the organization's "most important and successful collections" were ordered destroyed, including histories of humanity and Africa, and surveys of ancient monuments.

It was unclear who was responsible, he said. "We have launched an inquiry, consulting publications officers of the period, now retired, in order to discover the reasons which led them to take this decision and not to consider other options," the audit report quotes him as saying.

South African Ambassador Nomasonto Maria Sibanda-Thusi told the executive board: "We believe that some decisive disciplinary action is needed. The main player may have retired, but what about those that knew but chose to remain silent?"

According to the report, the destruction occurred in 2004 and 2005, when UNESCO's overflowing book storage warehouses in Paris were relocated to Brussels. Rather than pay to move 94,500 books, auditors reported, UNESCO officials ordered them destroyed. The books were turned to pulp for recycling, the audit says.

Nino Muñoz Gomez, director of UNESCO's Bureau of Public Information and chief of the publishing division, said at least half of the destroyed volumes were outdated and contained obsolete statistical data.

The audit notes some publications were out of date but says others "on historical or purely literary themes (poetry anthologies, stories from all lands in translation) were not at all affected by obsolescence." It says a "solution other than destruction" should have been considered, "such as free distribution to libraries."

Several irate African and Latin American ambassadors said libraries and schools in their impoverished countries would have been eager to receive comprehensive history books.

The auditors found at least 4,990 copies of the General History of Latin America — one-quarter of those published — were destroyed. Records show that pulping of the first six volumes — which sell for about $48 at the UNESCO bookstore — was ordered even as historians and authors were working on the final three volumes of the nine-book set.

In addition, more than 10,000 French and English copies of General History of Africa (about $72 each) were destroyed, as were 3,572 copies of The Different Aspects of Islamic Culture ($72 each) and 2,944 paperback copies of the French-language History of Humanity, a 1,500-page tome that sells for about $41.

The list of pulped publications also included books about the ancient Incan capital, Cuzco, in Peru, and the 2,000 Buddhist monuments at the ancient Burmese capital of Pagan.

Auditors made the discovery during a wide-ranging investigation of abuses and waste in UNESCO's book publication and distribution operations.

Because too many books often were ordered and others were never distributed properly, tens of thousands piled up in UNESCO's storage facilities at a cost of about $100,000 a year, until the agency decided to shift distribution functions to a Brussels company and move its stocks there.

Muñoz Gomez, who assumed his post in April 2005 and was chief of the publishing section for nine months while the book destruction was taking place, said he did not learn of it until early 2006, when a new employee showed him thousands of dollars in bills for the pulping.

He said he authorized payment of those bills "of several thousand euros each" but did not realize the magnitude of the operation. "All we knew is the bills were sent by the company and we had to pay the bills," he said in an interview.

He contacted the company to halt the pulping, he said, but "by 2006 there was nothing more to destroy."

Muñoz Gomez said he wrote in February to the now-retired chief of the publications section, requesting details on the decision to destroy the books, but has received no reply. He would not identify the former employee or provide information about current whereabouts.