Rhino heads and horns worth £428,000 stolen from Irish museum 18 April 2013 Last updated at 11:50 A gang of thieves have stolen rhino heads and horns worth up to half a million euros (£428,000) from an Irish museum. Three masked men entered the National Museum Archives building in Dublin at about 22:40 BST on Wednesday and tied up a security guard. The gang loaded the four heads, with eight horns, into a large white van. The security guard, who was not injured, managed to free himself and raise the alarm shortly after midnight. A police spokesman said the building on Balheary Road, Swords, has been sealed off for forensic examination. Smash and grab An incident room has also been set up at Swords Garda (police) station and officers have appealed for information about the theft. Nigel Monaghan, keeper of the museum's natural history division, said staff had taken the decision to remove its rhino horn collection from public display in 2011, following a spate of "smash and grab" thefts from museums across Europe. The artefacts had been placed in the museum's storage facility in Swords for safe keeping when the thieves struck. A statement issued on behalf of the museum said: "The stolen rhinoceros heads have a total of eight horns that have probably been taken to supply the illegal trade in powdered horn that is used in traditional medicines in the Far East. Poaching Their price is based on weight and the total amount stolen could have a street value in the region of 500,000 euros. The statement added that several species of rhino have been "brought to the edge of extinction" due to poaching in the wild, so in recent years thieves have begun to target museum and private collections. The National Museum of Ireland has exhibition centres spread across four locations. Three are in Dublin and the fourth is in County Mayo. Its natural history collection is housed on Merrion Street in Dublin city centre, close to the Irish parliament.