Ruby had joined the police's bomb disposal squad in June 2009. She had played major role in detecting around 41 cases during her stint with the squad.
"One of of her major detections was a brutal murder case in Khar East in 2015, in which she helped us to reach culprits by just smelling a slipper," police said in a video posted on its official Twitter handle, in honour of Ruby.
Ruby was suffering form carcinoma, a kind of cancer. She had undergone an operation in February and was provided radio therapy treatment for six times to overcome the deadly decease, a senior police official said.
Ruby's mortal remains were laid to rest with full state honours.
"Remembering Ruby, a star of our bomb disposal squad, whose contribution to the department are 'impawssible' to match! #RIPRuby," wrote Mumbai Police on Twitter.
Ruby's demise came after death four other police dogs- Caesar, Tiger, Max and Sultan in the recent past.