Gunshots drowned out applause at three separate high school graduation ceremonies across the United States. The shootings all happened in Louisiana, Michigan and Tennessee in less than 24 hours, resulting in one person dying and seven others being injured.

Riverdale High School (Tennessee)

The first incident went down on Wednesday night at the ceremony for Riverdale High School in Murfreesboro, Tennessee.

As the crowd was dispersing toward the end of the event, a 17-year-old shot and killed Hasani Brewer. Another 17-year-old, who was fighting with Brewer before the third teen opened fire, was also wounded. It’s worth adding that Brewer was a past graduate of the high school and the injured 17-year-old is a junior.

“This was not a random shooting,” Murfeesboro Public Information Officer Larry Flowers said. “The two victims and the shooter knew each other.”

The suspect will soon be arraigned on a first-degree murder charge in juvenile court.

Crossroads Alternative High School (Michigan)

Another incident soon followed the Tennessee tragedy in Grand Rapids, Michigan.

While Crossroads Alternative High School students were graduating on Thursday, “a large number of shots” were fired off outside the ceremony. While two deputies were on-scene serving security, the suspects were long gone when they got to the parking lot.

Two people were injured in the matter: a 16-year-old from Texas and a local 40-year-old. It’s unclear if the victims were connected to the graduation ceremony.

The suspects have not yet been identified, though the white Mercedes they fled in has been located and is being processed.

Hammond High School (Louisiana)

A third incident went down on Thursday evening in Hammond, Louisiana.

Four people attending Hammond High School‘s commencement ceremony suffered non-life-threatening injuries, though authorities notably “do not believe any juveniles were involved [or] struck in this incident.”

A suspect named Trent Thomas was tracked down on foot and taken into custody.

“We apologize to our families and to our students that this night, which should have been a very happy occasion for our graduates and their families, ended on such a sad note,” Melissa Martin Stilley, Tangipahoa Parish Superintendent of Schools, said of the incident.