MINNEAPOLIS (WCCO) — A 76-year-old man was taken into custody Sunday morning after refusing to let his girlfriend leave their residence and threatening her life, according to the Beltrami County Sheriff’s Office.

Authorities were called by the suspect at about 6:30 a.m. Sunday in Liberty Township, which is north and east of Bemidji, on what sounded initially like a medical emergency. The man was in a state of exhaustion and his girlfriend told authorities he had not slept in days due to complications from Lyme’s Disease.

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Officers made arrangements for the girlfriend to leave so the man could get some sleep.

About four hours later, the man called 911, was speaking gibberish and not making sense. He was also talking about harming himself with a firearm. Authorities said his girlfriend had returned to the residence and was being held hostage. The man refused to let her leave and was threatening her life.

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Officers responded to the residence, and observed that the suspect had a Derringer pistol in his possession.

After more than five hours of negotiations, the female hostage escaped the residence from a second story window by using a ladder. A few minutes later, the man exited the residence and was taken into custody without incident.

He was transported to Sanford ER for a mental health evaluation. His name has not been released.

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The Beltrami County Sheriff’s Office was assisted at the scene by Bemidji and Blackduck police, the Minnesota State Patrol, Bemidji Ambulance Service, Beltrami County Emergency Management and Communications and Bemidji Police Reserves.