On December 4, 1969, two members of the Black Panther party, Fred Hampton and Mark Clark, were killed during a police raid on an apartment in Chicago. Drugged by an FBI informant (who killed himself 20 years later), Hampton was allegedly shot and killed while asleep.

The incident was later connected to COINTELPRO, the FBI’s illegal counter-intelligence program. After a break-in at an FBI office in Pennsylvania, documents were leaked, including a floor plan of the apartment in which Hampton and Clark were staying.

After more than a decade of legal maneuvering and filing a lawsuit for civil rights violations, a settlement was reached and a group, including the mothers of both men, was awarded close to $2 million.

Elsewhere on December 4ths of the past? Psychiatrist W.H. Rivers introduced the public to the phenomena of “shell shock,” which is what we used to call Post-Traumatic Stress Disorder. The condition was once thought to affect only soldiers returning from war, but as more and more research was conducted, it became clear that the general public experienced it as well. And H to the Appy, B to the Irthday to Jay-Z, who turns 46.

Learn more about December 4 and watch more Today in History videos on Timeline.