Sharp-eyed police investigating a house robbery in Cape Town's Mowbray made an unexpected discovery of R10m worth of abalone on Friday, a spokesperson said.

Lieutenant Colonel Andre Traut said police were investigating a complaint that seven people had robbed the house in Strubens Road, but then they realised the house was being used as an abalone processing plant.

A search of the premises led to the discovery of the massive haul of abalone and equipment used to process it for exporting.

A man and a woman who claimed that they had been tied up by the seven robbers who had made off with abalone were arrested.

The two are expected to start the process of explaining themselves when they appear in court in Wynberg on Monday on charges of illegal possession of the marine mollusc, considered a delicacy.

A report released in September stated that the population of South African abalone, Haliotis midae, was declining at unprecedented levels with at least 96 million abalone stripped from the country's reefs over the past 18 years. 

Part of a R10m abalone haul in Mowbray, Cape Town. (Supplied)

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