Rhino heads and horns have been stolen from a warehouse belonging to the National Museum in north Co Dublin.
The items were taken late last night by three masked men from the premises in the National Museum Archives, Balheary Road, Swords.
Gardai were called shortly after midnight by a security man, who was tied up by the raiders.
A Garda statement said the three men loaded rhino heads and horns from the building into a large white van. It said the raiders were in the building for approximately one hour.
The security man, who was uninjured, later freed himself and raised the alarm.
“A Garda investigation has begun into the theft. The value of the property stolen is estimated to be in the region of €500,000. The crime scene is sealed off for forensic technical examination and an incident room has been set up at Swords Garda station,” the statement added.
In 2011, Europol said it believed an Irish organised crime gang had become one of the most significant players in the illegal global trade in rhino horns.
The gang, members of a large Traveller family, was believed to have been behind museum robberies in Italy, Germany and the UK in which rhino horns on display were stolen from facilities with little or no security measures.
It is believed the horns have been primarily sold into the Chinese medicines market. There is also an international underground collectors’ market.