Chinese farmer cracks open chicken's giant egg to find smaller one inside

A farmer in China has cracked open an abnormally large chicken's egg only to find a second one fully formed inside.

The bizarre discovery happened in front of a CCTV News camera after the farmer from Qinhuangdao city in the northeast called a reporter to investigate.

"I've never seen an egg within another egg in more than 60 years of farming," a farmer told the news station.

It is not the first documented discovery of a smaller egg inside one that is oversized, though experts say it is extremely rare.

"Though quite rare, it is well-known that occasionally a hen will lay an egg inside of an egg," Countryside Daily reports.

"The cause of this phenomenon is called a counter-peristalsis contraction and occurs while the hen is in the process of forming an egg in her oviduct."