5th » United States Army e.g U.S. Army Major Nidal Malik Hasan murders 13 and wounds 32 at Fort Hood, Texas in the deadliest 2009 Fort Hood shooting known as mass shooting at a U.S. military installation.
10th » Ships of the South and North Korean navies Battle of Daecheong called skirmish off Daecheong Island in the Yellow Sea.
21st » A 2009 Heilongjiang mine explosion called mine explosion in Heilongjiang province, northeastern China, kills 108.
23rd » The Maguindanao massacre occurs in Ampatuan, Maguindanao named Ampatuan, Maguindanao, Philippines
25th » 2009 Jeddah floods: Freak rains swamp the city of Jeddah, Saudi Arabia, during an ongoing Hajj pilgrimage. 3,000 cars are swept away and 122 people perish in the torrents, with 350 others missing.
27th » 2009 Nevsky Express bombing: A bomb explodes on the Nevsky Express train between Moscow and Saint Petersburg, derailing it and causing 28 deaths and 96 injuries.
29th » Maurice Clemmons Lakewood, Washington police officer shooting named shoots and kills four police officers inside a coffee shop in Lakewood, Washington.