WALNUT CREEK, Calif. (KGO) --Officials are working to determine who is setting fires in Walnut Creek.
Fire investigators say four suspicious fires are connected, including one from Thursday night.
One of the fires burned about half an acre in Arbolado Park, the exact location of a fire two years ago.
None of the fires have caused any serious damage so far.
Authorities are asking the public to report suspicious activity by calling 1-866-50 ARSON or 1-866-502-7766.