(CNN) Hundreds of Oklahoma inmates left prison Monday before their original sentences were over. And bipartisan lawmakers couldn't be happier.

In the largest mass commutation in US history, at least 462 non-violent inmates were released, officials said. A total of 527 inmates had their sentences commuted Friday, but 65 of them have detainers and will be released later.

The move is one of many prison reform efforts in Oklahoma aimed at reducing overcrowded prisons while helping low-level offenders build a life of self-sufficiency rather than reincarceration.

"Now is the first day of the rest of your life," Gov. Kevin Stitt told freed inmates.

He and other officials pledged help with what might be a challenging transition for many. "We really want you to have a successful future," the governor said.

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