About 40 masked attackers raided a disputed gold-mining project in northern Greece early on Sunday, setting fire to machinery and lightly injuring four security guards, police said.
The Skouries project in the Halkidiki peninsula has been the target of several protests by locals and activists who strongly oppose a gold mine being built because they say it would devastate the environment.
Police said the assailants entered the facility around 12.40 a.m local time (6:40 p.m. New York time on Saturday), causing extensive damage with firebombs and flammable liquid, and that 27 people had been detained.
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The Skouries project, an open pit copper-gold mine, is run by Hellas Gold, a subsidiary of Canadian firm Eldorado Gold that runs the Stratoni mixed sulfide project in northern Greece and is developing three gold projects in the region.
Mired in a sixth year of recession, Greece has been scrambling to attract foreign investment that will help kickstart growth in the economy.
Vancouver-based Eldorado employs about 680 people in Greece and expects to invest about $1 billion in the debt-plagued nation over the next five years.