CNN  — 

A 17-year-old gunman killed a sixth grade student and wounded five other people Thursday morning at Perry High School near Des Moines, Iowa, authorities said.

The five people wounded include four students and one school administrator, officials said. The school’s principal, Dan Marburger, was among the injured, according to officials in another school district where Marburger was an alumnus.

The attack was one of at least four mass shootings that have unfolded in the United States in 2024, according to the Gun Violence Archive. And it marks the second US shooting on school property in 2024, according to a CNN analysis.

The shooter, who was a student at the high school, was Dylan Butler, according to Mitch Mortvedt, assistant director of the Iowa Department of Public Safety Division of Criminal Investigation. A law enforcement official told CNN the shooter is dead.

Officers responded to the shooting within minutes and found several people at the high school suffering gunshot wounds, and then found the gunman with a self-inflicted gunshot wound, Mortvedt said during a Thursday news conference.

An improvised explosive device was also found during a search of the school and it was rendered safe by authorities.

The gunman was armed with a pump-action shotgun and a small caliber handgun, and had also made a number of social media posts around the time of the shooting, said Mortvedt, who did not offer more details on the contents of those posts.

Andrew Harnik/AP
Law enforcement officers are seen outside Perry High School on Thursday.

LIVE UPDATES: Shooting at high school in Perry, Iowa

Evidence suggests the shooter acted alone and authorities do not believe there are any additional threats.

“It all happened in the Perry High School, and it was before school started so there were not many students, and it’s our understanding that there was a breakfast program going on so there may have been students of different grades … in the school at that time,” Mortvedt said.

The attack erupted on the first scheduled day of classes of the new semester, according to the district. It followed a year in which more than 80 school shootings – more than in any year since CNN began keeping track in 2008 – were recorded, and came as Republican presidential candidates crisscross the state, vying for voters’ support ahead of the Iowa caucuses this month.

Though authorities have yet to identify the sixth-grader who was killed, Perry resident Jessica Conrad told CNN the child was “the sweetest boy, the one you want your kids to be friends with.”

The principal, Marburger, was identified as one of the wounded in a statement from the Easton Valley Community School district in eastern Iowa, where Marburger graduated. The district said it learned of his injury through “family connections we have in our area.”

Marburger has worked at schools in Perry for at least 25 years, according to the Perry Community School District’s directory.

Authorities responded within 7 minutes to a 7:37 a.m. call of an active shooter at the campus, Dallas County Sheriff Adam Infante had said earlier Thursday. “There was very few students and faculty in the building,” he said, noting classes had not yet begun.

The FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives confirmed their agents had responded to the high school, as did the Iowa State Patrol, Sgt. Alex Dinkla told CNN, and police vehicles from multiple cities. The FBI said it was assisting the Iowa Division of Criminal Investigation, which is the lead investigative agency in the case.

“The law enforcement response was swift and immediate,” Mortvedt said during Thursday’s news conference. “Roughly 150 officers from local, state and federal agencies responded within the hour.”

Perry is about 40 miles northwest of Des Moines and has a population of about 8,000, according to the US Census Bureau. The Perry Community School District — comprised of the high school, a middle school and an elementary school — serves about 1,800 students, its website says.

Charlie Neibergall/AP
A man and children leave the McCreary Community Building after being reunited following a shooting at Perry High School on Thursday.

Late Thursday morning, Iowa Gov. Kim Reynolds expressed support for the community, its students, teachers and families, writing on X, “Our hearts are broken by this senseless tragedy.”

Former South Carolina governor and GOP presidential candidate Nikki Haley similarly reacted, writing on the platform formerly known as Twitter, “No parent, student, or teacher should have to wake up and face news about a school shooting.”

“My heart aches for the victims of Perry, Iowa and the entire community,” Haley wrote on X.

Kris Brown, president of Brady United Against Gun Violence, a gun violence prevention organization, lamented the fact that gun violence plaguing the United States continues, saying in a statement, “New year, same horror.”

“2024 should not start this way for the students of Perry High School or any student in our nation,” Brown said, expressing support for the community. “This year – as with every year – we are resolved to end this deadly epidemic and free America from gun violence.”

This is a developing story and will be updated.

CNN’s Hannah Rabinowitz, Betsy Klein, Amy Simonson, Holmes Lybrand, Asher Moskowitz, Raja Razek, Aaron Pellish, Caroll Alvarado and Sharif Paget contributed to this report.