03/29/2011 07:30 pm ET | Updated Jun 16, 2011

Security Increased At Port Huron Northern High School In Mich. After Racist Hit List Found

A hit list found in a Michigan school's boys bathroom targeted eight black students and said something would happen March 29.

The Times Herald reports that extra police have been patrolling Port Huron Northern High School Tuesday, which is about an hour outside Flint, Mich.

Port Huron Schools Superintendent H. Ronald Wollen told the Detroit Free Press the list was vague:

"They didn't really get specific," Wollen said. "That's why we're going to have the police patrolling."

Administrators and police have been reviewing video footage, interviewing students and examining writing samples. Still, investigators are having a "difficult time pinpointing the person who wrote the comments on the wall," acting Police Capt. Jeff Baker told the Times Herald.

Wollen said the police investigation leads him to believe one or two students are responsible, the Detroit Free Press reports.

The school had a similar problem five years ago. Since then, students participate in ongoing sensitivity training.

Anonymous tip can be left on the police department's hotline at 810-987-6688. A cash reward is available for a tip that leads to an arrest.