Once-azure Greek coastline blackened by oil spill (DRONE VIDEO)

The sinking of an oil tanker near Greece’s largest port over the weekend has left a number of popular beaches closed. With thick black waves of foul-smelling liquid drifting further along the Greek Riviera, authorities are struggling to contain the leak.

The spill occurred early Sunday, when the Agia Zoni II tanker went down off the island of Salamis near the main port of Piraeus carrying 2,200 metric tons of fuel oil and 370 tons of marine gas oil.

Officials initially believed the spill could be contained within the area of leakage, but the slick reached the Athens suburb of Glyfada, miles away from the shipwreck. The shore stretching from Piraeus to Glyfada, along with a part of Salamis Island, has been placed under swimming ban until beaches have been cleaned.

"If someone had warned us even on Tuesday, we would have taken precautions," Glyfada Mayor Yiorgos Papanikolaou told Skai TV, adding he didn’t think the oil spill would extend so far. Some 180 metric tons of fuel have been mopped up from just four beaches in Glyfada, according to New York Times.

“A huge cleaning-up effort is under way and that three specialized companies have been contracted to deal with the spillage,” the Greek Observer reported citing the Shipping Minister Panagiotis Kouroumblis, who added that it would take up to 25 days for the beaches to return to normal. The Greek authorities have also asked the European Commission to send an anti-pollution vessel to help clean the spillage in the Saronic Gulf.

Clean-up crews were seen collecting blackened sand and stones as well as pieces of tar Thursday. About 20 ships are involved in the clean-up efforts.

© Kostis Ntantamis / Global Look Press

Environmentalists, however are not so optimistic. “It takes between five to ten years for nature to fight pollution, and to eliminate the consequences of the oil spill. For about five years there will be a disruption of the marine ecosystem,” environmental studies professor at the National Technical University of Athens, Kimon Chatzibiros, said.

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The WWF director in Greece, Demetres Karavellas‏ shared a photo of a tiny oil-covered bird on social media, saying“oil kills” and calling the pollution “an environmental crime.”

There were reportedly only two crew members out of 11-strong contingent aboard the vessel when the ship went down. They were arrested following the incident but later released on bail. “I’m very sorry for what happened,” the ship’s owner, Theodoros Kountouris, said, breaking down in tears while saying he’d done everything he could to prevent the leakage when ship started to go down.

On Friday, an Athens prosecutor brought criminal charges against the vessel-owning company and the crew for an allegedly breaching environmental legislation. The court will also look into relevant agencies responsible for dealing with the spill and to ascertain if they fulfilled their obligations.