2008 - 6,844 people are killed in 2008 in Mexico's drug war. (Mexican government, April 2010)
November 3, 2009 - The reported head of the Los Zetas drug cartel, Braulio Arellano Dominguez, is killed in a gun battle with Mexican forces in Soledad de Doblado.
December 16, 2009 - Arturo Beltran Leyva, head of the Beltran Leyva cartel, is killed in a shootout with Mexican forces in Cuernavaca.
2009 - The Mexican government reports 9,635 deaths in 2009 in the drug war. (Mexican government, April 2010)
January 2010 - Carlos Beltran Leyva is arrested by Mexican authorities in Sinaloa. He is the third Beltran Leyva cartel brother to be captured or killed in two years.
February 25, 2010 - Osiel Cardenas Guillen, head of the Gulf Cartel until his capture in 2003, is sentenced in Texas to 25 years in prison. He also is forced to turn over $50 million to the United States.
May 26, 2010 - Pedro Roberto Velazquez Amador, allegedly the leader of the Beltran Leyva cartel in San Pedro, is killed in a shootout with federal forces in northern Mexico.
June 11, 2010 - Edgar Valdez Villarreal, "La Barbie", an American citizen, is charged with trafficking thousands of kilograms of cocaine into the United States. between 2004 and 2006. He remains a fugitive with a $2 million reward for information leading to his capture.
June 25, 2010 - A leader in the Sinaloa cartel, Manuel Garibay Espinoza, is arrested in Mexicali, by Mexican police.
July 29, 2010 - Ignacio "Nacho" Coronel Villarreal, one of the leaders of the Sinaloa drug cartel, is killed in a military raid in Guadalajara's suburbs.
August 25, 2010 - The bodies of 72 migrants from South and Central America are discovered on a ranch in Tamaulipas state. It is believed the 58 men and 14 women were kidnapped by the Los Zetas cartel and killed for refusing to traffic drugs.
August 30, 2010 - Mexican authorities announce that they have captured alleged drug lord Edgar Valdez Villarreal, alleged head of the Beltran Leyva cartel. The American-born Valdez is known as "La Barbie" because of his blue eyes and light complexion.
September 10, 2010 - Mexican President Felipe Calderon tells CNN en Español, "We live next to the world's largest drug consumer, and all the world wants to sell them drugs through our door and our window. And we live next to the world's largest arms seller, which is supplying the criminals."
September 12, 2010 - A top leader in the Beltran Leyva cartel, Sergio Villarreal, is arrested in city of Puebla.
November 5, 2010 - Antonio Ezequiel Cardenas Guillen, aka Tony Tormenta, allegedly the head of the Gulf cartel, is killed in a shootout with Mexican forces in Matamoros.
December 10, 2010 - Nazario Moreno-Gonzalez, also known as "El Chayo," "El Doctor" and "El Mas Loco," The Craziest One," is killed as part of an operation in the Mexican southwestern state of Michoacan. Moreno-Gonzalez is one of the leaders and main founders of La Familia Michoacana cartel.
December 2010 - Mexico's Attorney General Arturo Chavez Chavez announces a death toll of 30,100 people in Mexico's four-year drug war.
January 2011 - The Mexican government releases a revised death toll of 34,612 citizens killed during the four-year drug war.
January 17, 2011 - Flavio Mendez Santiago, one of the original founders of Los Zetas, is captured near Oaxaca.
February 15, 2011 - U.S. Immigration and Customs Enforcement agents Jaime Zapata and Victor Avila, Jr. are run off the road in Mexico and attacked by a group of armed men who open fire. Zapata dies and Avila survives a gunshot wound to his leg. The Los Zetas drug cartel is suspected.
February 23, 2011 - Mexican soldiers arrest six members of the Los Zetas drug cartel, including Julian Zapata Espinoza, who is allegedly responsible for the death of U.S. ICE Agent Jaime Zapata.
March 5, 2011 - Alleged Los Zetas drug cartel member, Mario Jimenez Perez, is arrested in connection with Jamie Zapata's murder.
March 7, 2011 - Alleged Los Zetas drug cartel leader, Marcos Carmona Hernandez, is arrested.
March 31, 2011 - Mexico's Attorney General Arturo Chavez Chavez resigns, for personal reasons.
April 2011 - Several mass graves holding 177 bodies are discovered in Tamaulipas, the same area where the bodies of 72 migrants were discovered in 2010.