On Saturday South Korean workers armed with oil skimmers and containment fences struggled to clean up the worst oil spill ever of the country, just as part of the slick was heading towards shore where there is a nature preserve.

Tanker Hebei Spirit that was carrying 260,000 tons of crude oil was hit on Friday morning by a vessel that was transporting a crane. The accident occurred just 5 miles off Mallipo Beach. A slick of 20 km extended from the tanker.

According to coast guard, almost 11 miles of coastline were covered by oil, Reuters reported.

On Sunday the oil spill is expected to reach the area with marine farms and oyster beds.

Cheon Myeong-cheol, a Taean coast guard official, said: "A part of the slick reached the shores of Taean and onto the beaches. There are about 1,200 residents helping in the cleanup," L.A. Times quoted.

Taen region is known for its beautiful beaches and its national maritime park. The first batches reached near the region’s nature preserve and the national park, an important stop for migratory birds.

Song Myeong-dal, head of the maritime ministry's Information and Policy Monitoring team, said that all measures are being taken to prevent the oil reach marine farms.

South Korea deployed 23 naval vessels, 34 oil skimmers, containments fences, six helicopters and 67 patrol ships in the area to control the oil spill.

This is the worst disaster of South Korea since the end of the Korean War 1950-1953.

The Taen coast said that more personnel will be send on Sunday to control the spill.

Almost 1, 200 local residents were cleaning the rocks and removing washed up oil from the coast.

No major impact on marine life was yet recorded on the area where the spill reached shore.

According to a maritime ministry, the biggest slick was spreading in Mallipo Bay.

On Friday efforts to clean up were hampered by heavy winds and high waves.

The size of the leak is a third of the size of the one that was spilled in 1989 in Alaska's Prince William Sound by the Exxon Valdez.

The coast guard said that the two vessels that collided on Friday are owned by South Korea's Samsung Corp. No casualties were reported in the accident.

The tanker was anchored and was waiting to load the crude oil into boats from a nearby port when it was hit by the vessel that was carrying a crane.