In his book "Hitler's bomb", Rainer Karlsch says a reactor was functioning by the winter of 1944/45 and that nuclear weapons were being tested on a Baltic Sea island and Thuringia, central Germany, under the supervision of the

"The Third Reich was extremely close to winning the race to build the first working nuclear weapon," his publisher, Deutsche Verlags-Anstalt (DVA), said in a statement.

However the arm was not well-developed enough to be dropped by air.

Karlsch, whose book will be released here on March 14, maintains that he found "the first German nuclear reactor in working order" near Berlin and discovered documents on a project for a plutonium-based bomb dating from 1941.

According to DVA, his work is based on careful examination of building plans, aerial photographs, soil analyses, diaries of researchers linked to the project and reports by US and Russian spies.

Despite sabotage by the Allies and funding difficulties, Nazi Germany did succeed in producing "dirty bombs" which killed "several hundred" prisoners during tests in Thuringia.

They were nowhere near as devastating as the atomic bombs dropped by US aircraft on the Japanese cities of Hiroshima and Nagasaki, killing an estimated total of more than 200,000 people by the end of 1945.

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.