OWATONNA — Officials placed a southern Minnesota school on lockdown and called police when tensions over racist comments posted on social media boiled over.

Owatonna Senior High School officials said a large group of students started shouting at each other in a commons area Monday over the comments targeting black students that were posted on Snapchat Sunday.

Black students make up 8.5 percent of the school’s enrollment. The school is 73 percent white.

Owatonna police said two students received citations for misdemeanor assault of an officer, but there was no fighting among students and no one was injured.

School officials have identified five students they believe are responsible for the posts but have yet to determine how they will be disciplined.