Historical timeline for December 20

A mass stabbing occurs in a primary school in Zagreb, Croatia, in which a 7-year-old pupil is killed and six more are injured by a knife-wielding 19-year-old male.

Six people are killed and over 200 are injured when an anti-Islam activist drives a car into a crowd at a Christmas market in Magdeburg, Germany.

The United States Space Force becomes the first new branch of the United States Armed Forces since 1947.

Aerosucre Flight 157 crashes during takeoff from Germán Olano Airport in Puerto Carreño, Colombia, killing five people.

Elizabeth II becomes the oldest monarch in the history of the United Kingdom, surpassing Queen Victoria, who lived for 81 years and 243 days.

The Portrait of Suzanne Bloch (1904), by the Spanish artist Pablo Picasso, and O Lavrador de Café by Brazilian modernist painter Cândido Portinari, are stolen from the São Paulo Museum of Art in Brazil. Both will be recovered a few weeks later.

A gang of thieves steal £26.5 million worth of currency from the Donegall Square West headquarters of Northern Bank in Belfast, Northern Ireland, United Kingdom, one of the largest bank robberies in British history.

Macau is handed over to China by Portugal.

American Airlines Flight 965, a Boeing 757, crashes into a mountain 50 km north of Cali, Colombia, killing 159 of the 163 people on board.

A Missouri court sentences the Palestinian militant Zein Isa and his wife Maria to death for the honor killing of their daughter Palestina.

The United States invasion of Panama deposes Manuel Noriega.

War on drugs: The United Nations agrees upon and promulgates the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances, one of three major drug control treaties currently in force.

In the worst peacetime sea disaster, the passenger ferry Doña Paz sinks after colliding with the oil tanker MT Vector in the Tablas Strait of the Philippines, killing an estimated 4,000 people (1,749 official).

Pope John Paul II announces the creation of World Youth Day.

Disappearance of Jonelle Matthews from Greeley, Colorado. Her remains were discovered on July 23, 2019, located about 24 km (15 mi) southeast of Jonelle's home. The cause of death "was a gunshot wound to the head."

The Summit Tunnel fire, one of the largest transportation tunnel fires in history, burns after a freight train carrying over one million liters of gasoline derails near the town of Todmorden, England, in the Pennines.

With the approval of the State Council, China's two largest newspapers, the People's Daily and the Guangming Daily, publish in full for the first time the Second Chinese Character Simplification Scheme.

Assassination of Luis Carrero Blanco: A car bomb planted by ETA in Madrid kills three people, including the Prime Minister of Spain, Admiral Luis Carrero Blanco.

Koza riot: After a series of hit-and-runs and other vehicular incidents involving American service personnel, roughly 5,000 Okinawans take to the streets, clashing with American law enforcement in protest against the U.S. occupation of Okinawa.

The Zodiac Killer murders his first two officially confirmed victims, David Arthur Faraday and Betty Lou Jensen, on Lake Herman Road in Benicia, California, United States.