New Britain Police Chief William Gagliardi says 65-year-old Victor Valcarcel Sr. was arrested at his home without incident a mile away from the hospital.
Heavily-armed police surrounded the Hospital for Special Care and helicopters with search lights flew overhead after reports of gunshots.
Patients at the hospital are in therapy, recovering from brain and spinal cord injuries.
Wednesday night, they were in lockdown, after a gunman shot two people inside the hospital right outside of Hartford.
Both shooting victims survived and were rushed to local emergency rooms.
One has non-life threatening injuries, the other one is more seriously injured with life-threatening wounds.
No patients were injured.
(The Associated Press contributed to this report)
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