So when FEMA deals with bodies in an emergency, they bring in refrigerated storage containers. The bodies are stored for eventual release to the families or cremation.

After Maria hit Puerto Rico, FEMA was asked to bring in enough storage for nearly a thousand bodies. This was because there was an immediate need for that many.

FEMA is not updating the body count because of political pressure from the white house. The administration doesn't want their response to Maria to be unfavorably compared to the response to Katrina. Therefore most storm deaths are being reclassified as natural deaths to keep the numbers low. Now, they know that we will see through this at some point in the future but as long as they can control the reporting now, most people won't care if the numbers shoot up later.