SAN DIEGO (CBS 8)  — Don Parker was a sheriff's deputy for more than 20 years and rose to head of the Search and Rescue Detail. 

Now he is in the hospital being treated for a life-threatening cancerous brain tumor.  

Parker was diagnosed with a glioblastoma just a week ago and underwent surgery within days because of the severity of the tumor.  

A node was also discovered on Parker's lung, according to a GoFundMe page set up to help he and his family with medical costs.

The page also said Parker will undergo upcoming chemotherapy and radiation treatments.  

CBS News 8's Dominic Garcia reported from Escondido with more on Parker's battle.