Puerto Rico's prisons department says it is investigating the deaths of 53 inmates detailed in a report by the American Civil Liberties Union.
Corrections Secretary Carlos Molina Rodriguez says the probe's findings may be sent to the island's Justice Department if necessary.
Molina said in a statement Friday that the number of inmate deaths has dropped 40 percent over the last 17 months.
The ACLU released a report Thursday saying that some of the deaths that occurred between 2002 and 2008 potentially could have been prevented with better medical care.
All but one of those who died were in pretrial detention, and about three-fourths percent perished within their first week of confinement.
