Minneapolis ? A man accused of fatally hitting a Muslim teenager with his car last week in what’s being investigated as a possible hate crime had been diagnosed with schizophrenia, committed to a hospital and sometimes stopped taking his medications, according to court records and his family.

Ahmed H. Aden, 34, is charged with first-degree murder in the death of 15-year-old Abdisamad Sheikh-Hussein, whose legs were nearly severed when an SUV hit him Thursday in Kansas City, Mo. Aden initially said he lost control of the vehicle but later said he thought the teen was someone who had threatened him, investigators said.

The FBI won’t disclose why it is investigating the crash as a possible hate crime, but the teen was Muslim and Aden’s vehicle had anti-Muslim statements written on a window. However, Aden’s mother, Hawo Abdullahi of Minneapolis, said her son also was Muslim and, like the victim, was Somali.

“How can my son do a hate crime when he’s not mentally thinking straight?” Abdullahi told The Associated Press through an interpreter Monday, the same day her son appeared in court.

She expressed condolences to Sheikh-Hussein’s family, saying she wished she could have helped her son.

“All I can say to you is, I tried (to help) my son, I tried a couple of times to get him admitted to the hospital because he was mentally sick. But I wasn’t there. If I were there, this would not have happened,” she said. “I would get him into the hospital.”

When asked about claims Aden was mentally ill, a spokesman for the Jackson County prosecutor said the office does not comment on ongoing investigations. A message left for Sheikh-Hussein’s aunt was not immediately returned.

His mother and sister said he moved to Kansas City without their knowledge about a year and a half ago. Abdullahi said she believes Aden stopped taking his medication before Thursday’s accident. She said he may have reacted angrily after he was misunderstood and ostracized by others who didn’t know he was struggling.