A staff member at Harrison Education Center in Minneapolis was critically injured after police said he was assaulted at the school Tuesday morning.

Police have taken an 18-year-old man into custody.

Minneapolis Police spokesman John Elder said officers responded to a physical altercation at 9:45 a.m. at the center, an alternative high school for students with severe behavioral or emotional disorders.

The victim, Mohammed Dukuly, who is a paraprofessional, had “significant” injuries and was taken to HCMC in Minneapolis, police said.

Christine Hill, a spokeswoman for HCMC, said Dukuly was in critical condition. School district officials refused to divulge details about the incident, citing privacy laws.

“We are aware of an incident this morning at Harrison Education Center in which a staff member was injured and in need of emergency medical attention. Due to the nature of the incident the Minneapolis Police Department is involved,” according to an official statement issued by Minneapolis Public Schools.

“Any time an injury occurs we conduct a full investigation and we will do so in this case. However, we extend our thoughts to the staff member and their family,” the statement said.

Staff members have been attacked at Harrison before. In January 2016, a 17-year-old student was charged in with repeatedly punching the school principal, Monica Fabre, in the face, giving her a concussion. The student pleaded guilty to felony third-degree assault and gross misdemeanor assault. On Jan. 7, 2016, a 14-year-old boy was arrested in connection with the assault of a female teacher at the center.