Officers in Richmond received a tip that a man had said he wanted to harm Muslim community members, the Contra Costa Times reported on Sunday.
Detectives said they learned the man might have made an explosive device at his home.
Authorities evacuated nearby residents Sunday before serving a search warrant at the man's house and destroying the possible device. No one was injured.
Police said the man was arrested without in incident. His name and age were not released. No further details were released.