This is the biggest fear of any library, although, in this case, luckily, no one was hurt. The blaze at the main library for the Institute of Scientific Information on Social Sciences damaged or destroyed about 15 percent of the library’s 14 million documents (about 2.1 million items). The library has a number of rare Slavic texts, in addition to works on politics and economics that were removed from Germany after World War II. There are also many government documents, dating as far back as 1789, from various countries, including the U.S. Even though some of the materials, particularly United Nations documents, can probably be replaced, the damage is expected to hinder seriously the Institute’s role as a research center. Also, although the blaze has been extinguished, there is still a possibility that the building could collapse, due to structural damage and high temperatures. Arson has been suggested as a cause, but authorities claim that a short circuit likely started the fire. It is not clear, at this time, how much financial support the Institute will receive from Russian President Vladimir Putin to rebuild parts of the library and repair or replace the damaged materials.
http://sputniknews.com/russia/20150131/1017582632.html (additional photos, and also a video, of the blaze and efforts to put it out)