Flags flew at half mast at the Royal Newfoundland Constabulary's provincial headquarters in St. John's Tuesday, as the police force mourned the loss of former chief, Bob Johnston.

Johnston died Monday after a fight with a difficult to treat form of brain cancer, a disease he faced with optimism and grit.

"We feel robbed today," RNC Chief Joe Boland told reporters Tuesday afternoon.

"This is a sad day for our organization."

Johnston's career began in 1979 and spanned more than three decades, culminating in becoming chief in 2010. He served in the role until his retirement from the force in 2014.

Johnston on the job in 2014. (CBC)

Boland worked with Johnston for much of that time, recalling Johnston's early years as "a person that wanted to make a difference in this community," and who managed to do just that, even amid turbulent times on the force in the mid 1990s.

"If you were to try to blueprint your career, your life, you would look at him and say, 'this guy did it right,'" he said.

"At 60 years of age, it seems just wrong."

A public fight

Johnston was diagnosed with Stage 4 glioblastoma, an aggressive, incurable brain cancer, in early September 2017.

Tragically Hip frontman Gord Downie had the same cancer, which comes with an average survival rate of 18 months, post-diagnosis.

Johnston beat that average, making it close to two years.

In July 2018 he and his wife Gloria Johnston went public with his diagnosis. In an interview with CBC's Debbie Cooper he said, "I want to give people hope" by opening up about his life with brain cancer.

Watch the 2018 interview with the Johnstons below:

The former chief of the Royal Newfoundland Constabulary has taken on a devastating glioblastoma diagnosis. 10:35

He also spoke candidly about his and his family's decision to stay positive and savour each day as it comes.

"He never complained, which didn't surprise me on bit," said Boland.

"That's him, it was never about Bob."

Johnston received numerous accolades during his policing career, including an Order of Merit from the Governor General of Canada in 2012.

He is survived by his wife, two daughters and grandson, among other family, said the RNC.

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