Quito (agencies): An Ecuadorean judge ruled in an epic environmental case that Chevron Corporation was accountable for oil drilling pollution in a wide swath of Ecuador's northern jungle and ordered the oil giant to pay $9.5 billion in damages and cleanup costs.

The amount of $8.6 billion plus a legally mandated 10 per cent reparations fee was far below the $27.3 billion award recommended by a court-appointed expert but appeared to be the highest damage award ever issued in an environmental case.

But whether the plaintiffs including indigenous groups, who say their hunting and fishing grounds in Amazon River headwaters were decimated by lethal wastewater that also raised the cancer rate, can collect remains to be seen.

In a statement, Chevron called the decision "illegitimate and unenforceable" and said it would appeal.

Company spokesman Kent Robertson said that "the evidence of fraud on the part of the plaintiffs' lawyers is overwhelming."

"We intend to see that the perpetrators of this fraud are held accountable for their misconduct," he added.

The plaintiffs' lead attorney, Pablo Fajardo, called the 187-page judgment "a great step that we have made toward the crystallization of justice" but added that "we are not completely satisfied" with court-specified damage award. The plain-spoken native of the oil patch said that the plaintiffs were discussing whether to appeal.

The suit was initially filed in a New York federal court in 1993 against Texaco and dismissed three years later after the oil company argued that Ecuador was the proper venue to hear the case. Chevron bought Texaco in 2001 and the suit was refiled in Ecuador two years later.

Though it had only 47 named plaintiffs, the suit sought damages on behalf of 30,000 people for environmental pollution and illnesses that allegedly resulted from Texaco's operation of an oil consortium from 1972 to 1990 in a Rhode Island-sized oil patch dug out of virgin rain forest.

Monday's ruling was lauded by the environmentalist groups Amazon Watch and Rainforest Action Network as "proving overwhelmingly that the oil giant is responsible for billions gallons of highly toxic waste sludge deliberately dumped into local streams and rivers, which thousands depend on for drinking, bathing, and fishing."