Thomas Bonfanti, 63, of Northfield was charged with murder on Monday after shootings in which three people were killed. Washington County Jail via AP

A Machias woman who was wounded in a shooting rampage Monday was listed in critical condition Tuesday night at a Portland hospital.

Regina Hall Long, 49, of Machias was one of four people allegedly shot Monday by Thomas Bonfanti, 63, of Northfield, in Machias and Jonesboro. She was taken to Maine Medical Center for treatment. The other three were killed.

Investigators for the Maine State Police Major Crimes Unit are still trying to determine a motive. Bonfanti was arrested at the American Legion hall in Machias a short time after the shootings.

Killed in the rampage were 57-year-old Shawn Currey of Machias, 33-year-old Samuel Powers of Jonesboro, and 49-year-old Jennifer Bryant Flynn of Machias. State police said that Bonfanti was acquainted with each of the victims.

The Associated Press reported Bonfanti, who has been charged with murder, is scheduled to make his first court appearance in Calais on Wednesday morning.