Authorities are investigating the death of a 43-year-old Lawrence man in his cell at Bridgewater State Hospital Friday night, the state Department of Correction said.

Correction officials found Leo Marino unresponsive at 7:35 p.m. and “immediately initiated full emergency response beginning with CPR,’’ spokesman Darren Duarte said in a statement on Monday.

Marino was taken by Bridgewater firefighters to Morton Hospital in Taunton, where he was pronounced dead at 8:33 p.m., Duarte said. He said the state medical examiner’s office will determine a cause of death.

No further information was released about Marino’s death, which is not considered suspicious. State Police assigned to the Plymouth district attorney’s office are investigating, according to DA spokeswoman Beth Stone, who declined further comment.

The Lawrence man was admitted to Bridgewater State Hospital on Oct. 13 from the Essex County Correctional Facility in Middleton for observation, according to the Correction Department.

He was facing charges out of Newburyport District Court for allegedly operating under the influence of drugs and possession of a controlled substance. He was also charged in Lawrence District Court with assault and battery with a dangerous weapon and strangulation and suffocation.

Marino was civilly committed on Jan. 28 to the facility after he was found incompetent to stand trial in Essex Superior Court on the charges out of Lawrence.

Roderick MacLeish Jr., the attorney who filed a class action lawsuit on behalf of Bridgewater inmates in 2014, said Marino had “significant mental illness’’ but did not elaborate.

Bridgewater State Hospital is a medium-security facility whose population is made up of men civilly committed because of a mental health issue, prison inmates sent to the hospital because of mental health issues, and pretrial detainees who are undergoing a mental health evaluation.

According to MacLeish, Marino spent more than 250 hours in seclusion last month. The Department of Correction was unable to confirm that, but MacLeish said the length of time he spent in seclusion “raises troubling concerns.’’

“Given the level of monitoring there is supposed to be, it’s difficult to see how this happened,’’ he said. “Was he being watched?’’

Officials at Correction Department did not say whether Marino was supervised in the moments leading up to his death.

“The Department of Correction is undergoing a root cause analysis of this case as we do in any unexpected occurrence involving death or serious physical or psychological injury at Bridgewater State Hospital,’’ Duarte said. “We hope to have all questions answered as soon as possible.’’

MacLeish said Marino was in the Intensive Treatment Unit, which consists of 12 rooms behind locked steel doors where patients have limited privileges.

The area is monitored with surveillance cameras and staff check patients every 15 minutes.

Marino’s death follows that of at least three others at the embattled facility in which the patients died after the alleged improper use of physical restraints.

The family of one patient, Joshua K. Messier, who died in 2009, received a $3 million settlement from the state and a private mental health company.

A settlement reached in 2014 following the class action lawsuit called for a drastic reduction in the use of physical restraints and solitary confinement at Bridgewater, restricting such measures for emergencies only.

Leslie Walker, a lawyer and executive director of Prisoners’ Legal Services Massachusetts, said Bridgewater has long been understaffed and does not have enough mental health clinicians.

Jan Ransom can be reached at jan.ransom@globe.com. Follow her on Twitter at @Jan_Ransom. John R. Ellement can be reached at ellement@globe.com.