California police discovered a five-foot caiman named Mr Teeth guarding $100,000 (£62,000) worth of marijuana this week.
Police said they found the reptile, a smaller cousin of the alligator, on Tuesday when raiding Assif Mayar's home after a tip-off that he'd been selling drugs.
Police sergeant JD Nelson said guard dogs were a relatively common occurrence, "but alligators? You just don't see that every day."
Mr Mayar faces animal abuse charges after keeping Mr Teeth - bought in 1996 to commemorate rapper Tupac Shakur's death - in a two-by-eight-foot tank.
Mr Teeth died on Wednesday a day after being found, a zoo vet saying he had a "poor prognosis."
Caimans are usually found in the
wetland regions of central and South America and need plenty of space to live a full and healthy life.
Attacks such as yesterday's horrific murder in Woolwich didn't happen before the 'war on terror.' It's time we recognised the consequences of the conflicts we've unleashed