The police responded in force. At least 75 Jackson police units from the city of Jackson and the Mississippi Highway Patrol attempted to control the crowd while the firemen extinguished the fires.[3] After the firefighters had left the scene shortly before midnight, the police moved to disperse the crowd that had gathered in front of Alexander Hall, a women's dormitory.

Advancing to within 50 to 100 feet (15 to 30 m) of the crowd, officers at roughly 12:05 a.m opened fire on the dormitory.[4]

The exact cause of the shooting and the moments leading up to it are unclear. Authorities say they saw a sniper on one of the building's upper floors and were being shot at from all directions. Later, two city policemen and one state patrolman reported minor injuries from flying glass.[4] An FBI search for evidence of sniper fire found none.[5] The students said that they had not provoked the officers. The gunfire lasted for 30 seconds and more than 460 shots were fired by a reported 40 state highway patrolmen, who used shotguns from a distance of 30 to 50 feet.[2] Every window was shattered by gunfire on the narrow side of the building facing Lynch Street.[4]

The crowd scattered, and a number of people were trampled, or cut by falling glass. Phillip Lafayette Gibbs, 21, a junior, and James Earl Green, 17, a senior and miler at nearby Jim Hill High School, were killed, and twelve others were wounded.[4] Gibbs was fatally shot near Alexander Hall by buckshot, and Green was killed behind the police line in front of B. F. Roberts Hall, also by shotgun.[citation needed]

And South Carolina State, too.

https://en.wikipedia.org/wiki/Orangeburg_Massacre

Most victims sustained injuries from behind while fleeing or on the soles of the feet while lying on the ground.[64]