- Runoff Election Necessary in Brazil (Oct. 1): Incumbent president Luiz Inácio da Silva fails to win a majority in presidential election, taking 48.65% of the vote. He'll face Geraldo Alckmin of the Brazilian Social Democratic Party.
- Violence Intensifies Between Palestinian Factions (Oct. 2): At least 10 people are killed and more than 100 wounded in two days of fighting between Hamas and Fatah. The situation casts doubt that Palestinian president, Mahmoud Abbas, will be able to form a unity government.
- Monitoring Group Says IRA Has Stopped Terror Activity (Oct. 4): Report by the Independent Monitoring Commission finds that the Irish Republican Army has ceased paramilitary activity and has stopped sponsoring criminal enterprises.
- North Korea Tests a Nuclear Missile (Oct. 9): International outrage and condemnation follows the explosion of a nuclear device in the mountains of North Korea. President Bush calls the test a “threat to international peace and security.” The United Nations Security Council meets to consider sanctions on the country.
- Iraqi Parliament Passes Law to Divide Country into Regions (Oct. 11): Parliament votes in favor of a law that would allow provinces to unite and form semi-independent regions. Sunnis in parliament, who oppose the move out of fear that Shiites and Kurds will control most of the country's oil, boycott the vote.
- New Secretary General of the UN Is Appointed (Oct. 13): General Assembly approves the nomination of Ban Ki-moon, South Korea's foreign minister. He will begin his five-year term on Jan. 1, 2007.
- Security Council Agrees on Sanctions for North Korea (Oct. 14): Votes unanimously in favor of a resolution punishing North Korea for its reported testing of a nuclear weapon. Resolution bans the sale of materials that could be used to produce nuclear, biological, chemical, or ballistic weapons and allows authorities of other countries to inspect cargo entering and leaving North Korea. The resolution does not mention using military force against North Korea. After voting in favor of the resolution, China says it will not take part in cargo inspections.
- Iraqi Government Replaces Top Police Commanders (Oct. 17): Under pressure to control violence that has spiralled out of control, Prime Minister Nuri al-Maliki fires two police generals. The security forces have been criticized for having been infiltrated by members of Shiite militias.
- U.S. Says Campaign to Stem Violence in Baghdad Has Failed (Oct. 19): Maj. Gen. William Caldwell IV says attacks on U.S. troops have increased and sectarian violence has soared since the additional troops were deployed to the Iraqi capital in August.
- Militias Battle for Control of Amarra (Oct. 20): The Mahdi Army, which is connected to Shiite cleric Moktada al-Sadr, and the Badr Organization destroy police stations and bring the city to a standstill.
- Bush Speaks Candidly About the War in Iraq (Oct. 25): In a news conference, president acknowledges that the war is not going as planned, Iraqi troops are falling far short of expectations, and that the U.S. military may have to change tactics to succeed. “The fact that the fighting is tough does not mean our efforts in Iraq are not worth it,” Bush said. “To the contrary; the consequences in Iraq will have a decisive impact on the security of our country, because defeating the terrorists in Iraq is essential to turning back the cause of extremism in the Middle East.” Iraqi prime minister Nura al-Maliki also makes a speech, which seems to contradict Bush's plan.
- Reports Say Iran Is Enriching Uranium at Second Facility (Oct. 27): News report from Iran says that a second set of 164 centrifuges is in operation, doubling the country's ability to enrich uranium.
- U.S. Has Failed to Track Arms in Iraq (Oct. 29): Report by the Special Inspector for Iraq Reconstruction, which was requested by Republican senator John Warner, says the U.S. military has not appropriately tracked or maintained thousands of weapons that were sent to Iraq.
- President of Brazil Is Reelected (Oct. 29): Luiz Inácio Lula da Silva prevails over Geraldo Alckmin, 60.8% to 41.6% in the runoff election.
- Pakistan Military Targets Islamic School (Oct. 30): Missiles kill about 80 people who government officials say were militants when they destroy a school on the Afghanistan border. Officials also claim the school harbored members of al-Qaeda.
- North Korea Says It Will Return to Negotiations (Oct. 31): China announces that North Korea has agreed to resume disarmament talks with China, Russia, the U.S., and South Korea.
- U.S. Removes Checkpoints from Baghdad Streets (Oct. 31): Move follows demand by Iraqi prime minister Nuri al-Maliki. The U.S. military had set up checkpoints in an attempt to find a U.S. soldier who had been kidnapped.
- Gunman Kills Three at Amish School (Oct. 2): Charles Roberts lines up 11 girls, kills three of them and critically wounds eight before killing himself. It is the third shooting at a U.S. school in a week.
- Plane Crashes into Manhattan High Rise (Oct. 11): A single-engine plane carrying two people, one of them New York Yankees pitcher Cory Lidle, crashes into a 42-story building on the Upper East Side. Both men die in the crash. Several others, including residents of the building and firefighters, are injured.
- U.S. Charges an American with Treason (Oct. 11): For the first time in more than 50 years, the Justice Department charges Adam Yahiye Gadahn of treason, alleging he gave “aid and comfort” to al-Qaeda.
- Congressman Pleads Guilty; Does Not Resign (Oct. 13): Bob Ney, a U.S. Representative from Ohio, pleads guilty to corruption charges, saying he accepted thousands of dollars worth of gifts from lobbyist Jack Abramoff and his lobbying partners in exchange for attempts to legislate on their behalf. Despite pleas from Republican leaders, Ney does not step down.
- U.S. Population Hits New Milestone (Oct. 17): The U.S. population officially reaches 300 million. The population reached 200 million in 1967 and 100 million in 1915.
- Bush Signs Bill on Treatment of Detainees (Oct. 17): Presidents signs law, approved by Congress in September, that sets up military commissions to try terrorism suspects and creates rules for interrogating them.
- New Jersey Court Rules in Favor of Gay Couples (Oct. 25): State's highest court declares that same-sex couples are entitled to the same legal rights as heterosexual couples. Court, however, says that the state legislature must decide whether or not the unions can be called marriages.
- Bush Signs Legislation to Build Border Fence (Oct. 26): Border security law calls for a 700-mile fence between the U.S. and Mexico and other provisions to enhance barriers to illegal border crossings.
- Google Agrees to Buy YouTube (Oct. 9): The online search giant will pay $1.65 billion in stock for YouTube, a video-sharing website that has exploded in popularity, with users watching about 100 million videos each day.
- Earthquake Strikes Hawaii (Oct. 15): Quake with a magnitude of 6.6 hits the Island of Hawaii. It is the largest earthquake since 1983.
- Dow Reaches New Height (Oct. 19): The Dow Jones industrial average closes higher than 12,000 for the first time.
- Five Firefighters Die on Duty (Oct. 26): Four U.S. Forest Service crew members die while fighting a wildfire in California, which officials believe was set by an arsonist. More than 40,000 acres are burned and 34 homes are destroyed. (Oct. 31): A fifth firefighter dies.
- NASA Approves Mission to Repair Hubble Telescope (Oct. 31): Astronauts will fix and upgrade the telescope during a 11-day mission in 2008.