Thousands of hectares of farmland have been poisoned

The country's Environment Minister, who visited the sight within hours of the massive spill, says there is no risk to human life.

The main bulk of the contamination is still a few kilometres from the park itself and temporary dams have been built to try to stem the flow of what has been called a stream of poison.

A lot of agricultural land has been affected and crops will be lost, but by far the biggest outcry has come from environmental groups like Greenpeace, who are concerned about the welfare of Europe's largest natural reserve where hundreds of species of flora and fauna flourish as nowhere else on the continent.

They have described the accident as a crime against nature and want the Spanish Attorney General to take legal action against the foreign group that owns the mining company where the accident took place.

A Do�ana park spokesman identified the company operating the reservoir as Seville-based Minas de Aznalcollar.

Environmental groups say they had warned before about a disaster waiting to happen, but were ignored.