Spanish energy firm Repsol began searching for oil Tuesday in the waters off the Canary Islands, a top holiday destination, despite objections from environmentalists and the local government.
Oil exploration vessel Rowan Renaissance started drilling at dawn some 50 kilometres (30 miles) from the islands of Lanzarote and Fuerteventura, off the west coast of Africa, a Repsol spokesman said.
The prospecting is expected to last about 60 days, he added.
Spain's Industry Ministry in August authorised Repsol to search for oil in the region at three locations at depths ranging from three to seven kilometres.
The company estimates its chances of finding oil in the region are of 17-19 percent and plans to invest 350 million euros ($438 million) in the oil exploration.
But locals and green groups oppose the oil exploration. They fear Repsol's prospecting will harm local flora and fauna such as dolphins and disrupt the tourism industry that is vital to the area's economy.
"The government is protecting a private company, Repsol, to attack resources that are ours," said the head of the nationalist regional government of the Canary Islands, Paulino Rivero.
Fearing a loss to the tourism industry, his government called a referendum to ask residents if the archipelago should change its environmental and tourism policies for the sake of oil and gas exploration, but the national government blocked that in the courts.
The archipelago is proud of its green credentials.
El Hierro, the smallest of the seven islands that make up the archipelago, claims to be the first 100 percent renewable island in the world thanks to wind a large wind farm.
Rivero has accused the central government of showing preferential treatment to the Balearic Islands, a region run by the ruling Popular Party and which is also the target of an oil exploration project.
Prime Minister Mariano Rajoy has said his government would not allow oil exploration off the Balearic Islands if it presented the slightist environmental risk.
Spain imports nearly 80 percent of its energy and the central government argues it can no longer afford the luxury of holding back business or wasting natural resources.
Greenpeace activist hurt
Repsol has promised to take steps to protect the environment and says the project will create jobs in the islands, where unemployment is over 30 percent.
Under the terms of the licence, Repsol must provide a deposit of 20 million euros ($25 million) "to cover its environmental responsibilities".
It must stop its explorations if an earthquake stronger than magnitude 4.5 strikes the region.
A Greenpeace activist was hurt Saturday when the Spanish navy intervened during fresh protests against the exploration project.
The propellor of a boat cut and broke a 23-year-old Italian woman's leg after she fell overboard during the dawn clash, according to Spanish authorities.
The Spanish defence ministry said the navy believed the activists were trying to board the Rowan Renaissance, and had moved in to halt three Greenpeace boats. However, the activists say they intended to carry out a "peaceful protest".
The clash with the Spanish navy vessels on Saturday came just one day after rallies against the oil exploration were held across the Atlantic archipelago, whose beaches are a popular draw for foreign tourists from Britain, France and elsewhere.
Protests against the search for oil are scheduled to take place again on November 30.
A coalition of groups gathered under a "Rave Canaries" collective are planning to send a flotilla of boats that day to the area where Repsol is searching for oil.
The Canary Islands are Spain's third most popular destination after the Catalonia region including Barcelona, and the Balearic Islands.
The archipelago received 10.6 million foreign visitors last year, 17.5 percent of the total number of visitors to Spain.
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