The San Diego Police Department said "out-of-town" family members immediately called police when they found the body in a home in Zion Avenue at around 11.45am (7.45pm UK time) on Saturday.

Sky News's US partner network, NBC News, reported the body is believed to be female - but no other physical details have been confirmed.

An official identification will take place in due course.

The police department's homicide investigations team was called in, given the "unusual location" where the body was found.

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"Detectives are continuing to gather information to understand what happened and why the body was inside the freezer," police said.

It's unclear if any traumatic injury was involved, with the state of the body making it difficult to immediately determine any cause of death.