RIO DE JANEIRO -- A cargo ship grounded off the coast of Brazil has begun leaking oil, the country's environmental enforcement agency said Friday.

A thin spill of oil extended as far as 830 metres (2,720 feet) from the partially submerged Stellar Banner, according to the Brazilian Institute of the Environment and Renewable Natural Resources.

The captain of the ship detected water entering the cargo compartments on Monday and ran the ship aground to prevent it sinking. It was located about 100 kilometres (60 miles) offshore of Sao Luis. Crewmembers were removed from the ship.

The vessel, operated by South Korea-based Polaris Shipping, was carrying 300,000 tons of iron ore destined for Qingdao, China.

Polaris declined to respond to a request for comment.