Attorney General William Barr directed leaders of the federal prison system to increase the use of home confinement for certain inmates as the number of cases of coronavirus in the nation’s corrections system continues to multiply.

At a news conference Thursday in Washington, D.C., Barr told reporters that he had sent a memo to the Bureau of Prisons, telling officials there to increase the use of the program, which will likely see some older and especially vulnerable inmates released from prison early.

Barr said the measure was being done to try to “control the spread of this infection.”

Six inmates and four Bureau of Prisons employees had tested positive for the coronavirus as of Wednesday, as the Bureau of Prisons continued to implement strict measures to stave off the spread of the virus, including a ban on most visitors and a two-week quarantine for all new inmates entering a facility.

It was not immediately clear what inmates among the more than 175,000 in federal custody will be eligible for the expanded early release and home confinement program.

Barr said that he had asked the Bureau of Prisons last week to assess if it was possible to expand the use of home confinement “particularly for older prisoners who had served substantial parts of their sentence and no longer posed a threat and may have underlying conditions that make them particularly vulnerable.”