The island is infamous for the biological warfare experiments carried out there during the Second World War. To test the effectiveness of anthrax as a weapon some 60 sheep were released and bombs containing anthrax spores were dropped on the island. All the sheep died and all landings on the island were strictly prohibited for over 50 years
In 1986 the government instructed an English company to clean up the island. 280 tonnes of Formaldehyde diluted with seawater were sprayed over the island. After the operation sheep were again released – they showed no ill-effects and in 1990 the island was declared safe.