One specimen nicknamed "Oymiakon"－believed to be a 1-year-old female that lived between 28,000 B.C. and 38,000 B.C.－was being shown outside Russia for the first time since its discovery in the Siberian permafrost in 2004, organizers said.

Only her tusk-less head was uncovered, and the rest of the remains may have decomposed or were eaten by other animals, said zoologist Lin Chun-tsong.

The second mammoth, called "Yukagir," a 40-year-old male that lived around 18,000 B.C., is complete with two long curving tusks, hairy head and part of a leg. It was first seen by the public at Japan's Aichi Expo in 2005, after being excavated in 2002.

The mammoth remains were provided by Russia's Sakha Republic, where they were discovered. The exhibition will run through Nov. 4.

Police in Durham, northeast England, said on July 11 they had arrested a 51-year-old man over the theft of the First Folio edition of 1623, which scholars consider one of the most important printed books in the English language.

It was among seven centuries-old books and manuscripts stolen in December 1998 from a display case at the Durham University library in northeast England.

The First Folio was published seven years after William Shakespeare's death and was the first collected edition of his plays. Some 750 copies were printed, and about a third have survived, though most are incomplete. Only about 40 complete copies of the book are known to exist, most in museums or public collections.