2001 was dominated by the September 11 attacks against the United States by Al-Qaeda, which killed 2,977 people and instigated the global war on terror. The United States led a multi-national coalition in an invasion of Afghanistan after the Taliban government did not extradite Al-Qaeda leader Osama bin Laden. Internal conflicts, political or otherwise, caused shifts in leadership in multiple countries, which included the assassination of Laurent-Désiré Kabila in the Democratic Republic of the Congo, the Second EDSA Revolution in the Philippines, the massacre of the royal family by the crown prince in Nepal, and civil unrest in Argentina. Other notable political events were an escalation in the Israeli–Palestinian conflict, the storming of the Indonesian parliament, the Hainan Island incident between China and the United States, an insurgency in Macedonia, and a terrorist attack on the Parliament of India that began the 2001–2002 India–Pakistan standoff. Space milestones in 2001 were numerous, the most notable being the first spacecraft landing on an asteroid, the deorbit of the Russian station Mir, American entrepreneur Dennis Tito becoming the first space tourist, the discovery of 28978 Ixion in the Kuiper belt, a flyby of Io by the U.S. Galileo probe, and the first discovery of an atmosphere on an exoplanet. In addition, the year witnessed the first sequence of the human genome, the first self-contained artificial heart, and the first clone of a human embryo. 2001 was designated as International Year of Volunteers by the United Nations. Health and society The world population on January 1, 2001, was estimated to be 6.190 billion people, and it increased to 6.272 billion people by January 1, 2002. The average global life expectancy was 66.8 years, an increase of 0.3 years from 2000. The rate of child mortality was 7.58%, a decrease of 0.26% from 2000. 28.25% of people were living in extreme poverty, a decrease of 0.88% from 2000. The number of global refugees in 2001 was approximately 12 million. 500,000 were settled over the course of the year, but the same number of people were displaced in other locations, causing the number of refugees to remain largely unchanged. The largest sources of refugees were from Afghanistan and Macedonia. The number of internally displaced persons decreased from 21.8 million to 19.8 million in 2001, with the most affected areas being Afghanistan, Colombia, and Liberia. The World Health Organization (WHO) recognized mental health as its health concern