It seems the king of the ocean has a sweet tooth.

A man dressed in a blue and white shark onesie was one of two people who held up a petrol station near Christchurch overnight.

The pair made off with a haul of confectionery around 2:20am, after threatening BP Rolleston staff - armed with a hammer and a knife.

At approximately 2:20am this morning two men entered the BP in Rolleston, Canterbury, armed with a hammer and a knife.

Polie said they smashed a glass shelf which startled the attendant, who retreated to the staff room, where another colleague was having their break.