EDEN PRAIRIE, Minn. (AP) — A Minnesota man was charged Monday with aiding the suicide of his wife, who was reportedly suffering from unexplained pain that could not be relieved with medication.

Thomas Houck, 61, of Eden Prairie called 911 last Thursday to report that he woke up in the middle of the night to find his wife had "euthanized herself" with nitrogen, according to a criminal complaint.

Eden Prairie police arrived to find the woman dead with a plastic bag over her head and a tube running from a nitrogen tank into the bag. The complaint said that what appeared to be a handwritten note was nearby that said she couldn't endure any more pain.

Houck initially told authorities he helped his wife research suicide methods and accompanied her to the store to buy supplies, according to the complaint. He later allegedly admitted he helped his wife make a hood out of the plastic bag, based on information the couple found online.

He also later told authorities that he held the bag over her head and turned on the nitrogen gas tank as she died. When the tank was empty, he felt that his wife had no pulse, the complaint said.

Houck is scheduled to appear in court Tuesday. Online court records do not list an attorney to comment on his behalf.

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