PORTLAND, Maine — Police are searching for the person who allegedly harassed and pulled a knife on four black students in Portland.

The victims told police they were waiting for a bus Friday outside Casco Bay High School on Allen Avenue when a white teenager made racist comments at them, assaulted two of them, and then pulled out a knife.

The superintendent said he is relieved the students were not seriously hurt.

He is taking steps to keep students safe at the school.

“We’ll have an enhanced police presence at Casco Bay at dismissal and at arrival times for the foreseeable future, also I met with Principal Pierce this morning to talk about what we can do for the long haul to make sure our students are safe,” Portland Superintendent Xavier Botana said.

The students described their attacker as a white male, about 17 years old with patchy facial hair. He was wearing a black Insane Clown Posse hat and a camouflage backpack.

In an open letter to the Portland public schools community, Botana praised the four students for how they conducted themselves.

“They were remarkably mature and supportive of each other during a frightening time,” Botana wrote. “They stood up to the alleged assailant, took appropriate steps to be safe, and provided authorities with the necessary information to bring the attacker to justice.”