A discovery about the way HIV attacks the immune system could pave the way for the development of new treatments.

The Taliban have released a video that purports to show an American soldier captured in Afghanistan last June.

Kyrgyzstan's interim leader has thanked Russia for "significant support" in exposing what she called the crimes of the previous regime.

The rescue operation continues in Brazil, as hundreds of workers scramble to find residents buried by a landslide near Rio de Janeiro.

Barack Obama and his Russian counterpart Dmitry Medvedev have signed a new nuclear arms reduction treaty to cut US and Russian arsenals.

A solar-powered aeroplane designed to fly day and night without fuel has made its first test flight above the Swiss countryside

Swarms of locusts have invaded an outback town in Queensland, damaging vegetation and crops.

A Taiwanese boy looks set to become a singing sensation after performing Whitney Houston's I Will Always Love You on a TV talent show.