Patrick Kiely, 29, pleaded guilty Monday to a theft charge after earlier denying any involvement in the Feb. 20 incident at the Castle Museum in Norwich, the Norfolk Eastern Daily Press reported Monday,
Police said CCTV cameras recorded four men smashing the glass case around the rhino head and running off with the object.
The gang dropped the head when museum staff confronted them on their way out of the facility.
Kiely is serving a six-year prison sentence from a conviction earlier this year for the theft of about $24 million worth of jade artifacts from the Fitzwilliam Museum in Cambridge, England.
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