The Dead: Even Bones of, Caused Uncleanness
Source: TTT
Numbers 19:16
Anyone in the open field who touches someone who has been killed by the sword or has died of natural causes, or anyone who touches a human bone or a grave, will be unclean for seven days.
2 Chronicles 34:5
Then he burned the bones of the priests on their altars. So he cleansed Judah and Jerusalem.