John Olivarez spent 23 years protecting his city. He's a long time Edinburg police officer, and now he's fighting for his life at MD Anderson in Houston.

Cancer is such an ugly thing. What it does to our bodies and to even the strongest among us.

"These last couple of days, his health took a major dip. He's in intensive care right now," Olivarez's cousin, Myra Palomin said.

If you're from Edinburg, chances are you know Olivarez. He was a marine, then joined the police force, serving Edinburg for the majority of his adult life.

Olivares started more than 20 years ago, as a street cop, then joined the SWAT team.

"John was assigned to the FBI Task Force. So he's one of our task force officers, which is what I consider elite investigators. Someone who is willing to provide the highest level of service to this community," Edinburg Police Chief Jaime Ayala said.

Olivarez has been shot at, but that never stopped him. Last November, cancer finally did what criminals could not.

His family says he was diagnosed with large B-cell Lymphoma that has since spread to his brain. He and his immediate family have been going back and forth between Edinburg and MD Anderson in Houston for months.

"It's very difficult for our blue family here, to know what he's going through, to know he is fighting for his life," Ayala said. "He's in a position now, where he needs our help. He needs our prayers. His family needs our help, so anything the community can do to support John and his family would be extremely appreciated now, not only by us but by the family," 

Olivarez is currently on mechanical support in the ICU. 

A GoFundMe page has been set up for Olivarez and his family. To donate, click here.

Watch the video above for the full story.