AUGUSTA -- Michael S. Norton of South Portland died of a single gunshot wound to the neck and jaw, according to the state Medical Examiner's Office.

The office released the cause of death this afternoon. The full results of the autopsy, conducted Monday by Deputy Chief Medical Examiner Dr. Marguerite Dewitt, are not yet available.

Norton, 29, died early Monday morning, following a three-hour standoff at his house on Main Street.

Police had responded to the house Saturday and again on Sunday because of reports from Norton's family members that he was suicidal. He was shot around 2 a.m. Monday after apparently coming out of his house armed with a knife.

The incident is under investigation by the Maine Attorney General's Office.

11:56 a.m.

AUGUSTA -- The state Medical Examiner's Office says an autopsy has been completed for the man shot and killed by South Portland police Monday, but the cause of death has not yet been released.

Michael S. Norton, 29, died early Monday morning, following a three-hour standoff at his house on Main Street. Police had responded to the house Saturday and again on Sunday because of reports from Norton's family members that he was suicidal. He was shot around 2 a.m. Monday after apparently coming out of his house armed with a knife.

The incident is under investigation by the Maine Attorney General's Office. Deputy Chief Medical Examiner Dr. Marguerite Dewitt conducted the autopsy on Monday in Augusta.