Updated

An 80-year-old female patient was fatally stabbed early Friday at a northwestern Indiana hospital and her 88-year-old husband was later found stabbed to death inside their home, authorities said.

A middle-aged man is in custody and investigators believe he is responsible in the deaths at Methodist Hospital Southlake in Merrillville and the home in Gary, Gary Police Chief Wade Ingram said.

Margarine and James Haywood both died from multiple stab wounds, according to the Lake County coroner's office. The deaths have been ruled homicides.

The hospital was placed on lockdown for about four hours after the stabbing of Margarine Haywood about 12:30 a.m. Friday.

Ingram said during a news conference the person in custody knew both victims, but declined to give details about their relationship. He provided no other details.

"We do have one person in custody who we think is responsible for those acts," he said.

Merrillville police Detective Robert Wiley said the attack inside the hospital wasn't a random act.

"This isn't just some person off the street walking into a random room and harming a patient," he said.

Wright Alcorn, vice president of operations for The Methodist Hospitals, said the Merrillville hospital was secure following the attack.

"Staff and patients are safe, and that the hospital is operating as usual," he said.

Wiley said off-duty officers working security at the hospital in the town just south of Gary were among the first to respond to the reported disturbance in the woman's room. Wiley said Merrillville police soon asked Gary officers to check out the Gary home.

Ingram said his department's SWAT team was activated and the person believed responsible for the attacks was found in Gary about 5 a.m. It wasn't immediately clear when James Haywood was attacked.