A new government report finds 25 percent of drug overdose deaths in 2015 involved heroin, triple the percentage in 2010.

The National Center for Health Statistics found the percentage of overdose deaths from prescription opioids such as oxycodone and hydrocodone decreased to 24 percent in 2015, from 29 percent in 2010, Reuters reports. Cocaine was associated with 13 percent of overdose deaths in 2015, up from 11 percent in 2010.

The four states with the highest drug overdose deaths in 2015 were West Virginia, New Hampshire, Kentucky and Ohio. Overdose death rates increased for all groups, but the sharpest increase was among those ages 55 to 64.