SOMERS (AP) — Connecticut has closed the maximum security prison that once housed the state's death row.

Gov. Ned Lamont announced Friday that the Northern Correctional Institution, the state's highest security prison, was taken out of service three weeks ahead of the state's target date of July 1. The decision to close the prison was announced in February.

Northern is the first of three prisons the Correction Department plans to shutter amid lower crime rates and an inmate population that has declined during the pandemic. The state has yet to name the other two.

The state's inmate population has been hovering around 9,000 in recent weeks, a drop of about 3,400 people over the last 15 months.

Northern, which was designed in pods to keep high-security inmates isolated, once housed more than 500 prisoners, but has not had more than 100 in over a year.

In February, a lawsuit filed on behalf of prisoners alleged the use of prolonged isolation and in-cell shackling was violating the rights of mentally ill inmates. This week the General Assembly passed legislation banning the use of solitary confinement in most cases and the use of certain restraints.

The last of Northern's inmates was transferred to other high-security settings on Monday, Lamont's office said.

“Spending millions of dollars annually to operate facilities for a population that continues to get smaller and smaller is not a good use of resources, especially as we work to reduce the cost structure of state government,” Lamont said.

There were no layoffs associated with the closure and the 175 workers who staffed Northern have been transferred to nearby prisons, Lamont's office said.

Northern opened in 1995 and the state’s death row was moved there the same year. The state abolished its death penalty in 2015 after having executed only one person — serial killer Michael Ross in 2005 — since 1960.