In a highly unusual move, the US Centers for Disease Control and Prevention is not counting two measles-associated deaths reported by the state of Pennsylvania in its measles death tally, saying it doesn’t have enough information to determine whether measles caused or contributed to the fatalities.

The decision to exclude the deaths from the weekly update came from the CDC’s new director, Dr. Erica Schwartz, according to two people with knowledge of the decision.

The move escalates a feud between US Department of Health and Human Services Secretary Robert F. Kennedy Jr. and the state’s Democratic governor, Josh Shapiro, as the Keystone State seeks to extinguish a growing measles outbreak there.

Pennsylvania health officials have said they thoroughly investigated the details of both deaths before announcing them.

“Every reported measles case is thoroughly reviewed to confirm it meets the Centers for Disease Control and Prevention’s (CDC) case definition for a measles case. To date, DOH has provided all required epidemiological data to the CDC regarding the two measles-associated deaths in Pennsylvania,” said Neil Ruhland, press secretary for the Pennsylvania Department of Health.