About 25% of the inmates in Los Angeles County Jail have been released to try to prevent a COVID-19 outbreak behind bars, Sheriff Alex Villanueva said Monday morning.

That amounts to about 4,200 inmates who have been released since the pandemic began, the sheriff said in a news briefing.

“In the wildest dreams of the ACLU and all of the different groups who have been activists in that regard about the jail system, they never would’ve thought that would’ve been possible,” Villanueva said.

The goal of releasing inmates is to provide space within the jails for quarantining and isolation, according to the sheriff. The department now has the ability to separate inmates and move them around the system without exposing them and others to the virus, Villanueva said.

So far, a total of 676 Los Angeles County Jail inmates have been quarantined, 11 have tested positive for the coronavirus and 28 are under medical isolation, Villanueva said. That’s compared to hundreds of inmates who have tested positive in other jail systems such as the ones in the Chicago and New York area.

The LASD had to develop criteria for releasing inmates on the fly, Villanueva said. Some of the categories have included people with 30 days or fewer on their sentences, those in pretrial detention, those behind bars for technical parole violations and those at risk because of age or prior condition.

Of the inmates remaining behind bars, the overwhelming majority are there for violent offenses, according to the sheriff. About 1,200 inmates alone are being held on murder charges, he said.

“We’ve picked all the low-hanging fruit,” Villanueva said.

Even as inmates have been released, crime is down in LASD patrol areas because of stay-at-home orders, according to the sheriff.

Violent crime is down more than 9%, property crimes are down more than 15% and calls for service are down 12%, representing “very large statistical shifts,” Villanueva said.

City News Service contributed to this report.