An indignant federal appeals court ordered the government Thursday to keep paying benefits to hundreds of Vietnam veterans afflicted with a type of leukemia that has been linked to the defoliant Agent Orange.

    The ruling involved veterans suffering from chronic lymphocytic leukemia, a disease that the Department of Veterans Affairs found in October 2003 to be connected to Agent Orange exposure. That finding meant the government was required to provide benefits, but the department argued that it owed payments only from October 2003 forward, rather than from when a claim was filed.

    U.S. District Judge Thelton Henderson disagreed in 2005 and ordered retroactive benefits, which the department began to make as it appealed the ruling. The Ninth U.S. Circuit Court of Appeals in San Francisco upheld Henderson on Thursday and said it hoped that "obstructionist bureaucratic opposition will now cease.''

    It is hard to understand why the department "continues to resist . . . the payment of desperately needed benefits to Vietnam War veterans who fought for our country and suffered grievous injury as a result of our government's own conduct,'' said Judge Stephen Reinhardt in the 3-0 ruling.

    Agent Orange, which contains the lethal chemical dioxin, was sprayed by U.S. forces in Vietnam from 1965 to 1971. The herbicide was banned by the Environmental Protection Agency in 1979 and has been the subject of numerous medical studies and lawsuits.

    Since Henderson's order took effect, the government has paid $14 million in retroactive benefits to 498 veterans or surviving spouses and children, said plaintiffs' attorney Barton Stichman of the National Veterans Legal Services Program. He said he expects those figures to double when all payments are made.

    Stichman said the plaintiffs have been frustrated by the department's review process, which has taken a year to dispose of half the claims. Henderson will hold a hearing Monday on whether to hold the government in contempt of court.

    The Department of Veterans Affairs considered only one disease, a skin condition called chloracne, to be linked to Agent Orange when a nationwide lawsuit on veterans' behalf was filed in San Francisco in 1986. It required veterans suffering from any other disease to prove it was caused by the defoliant to receive benefits.

    Henderson rejected that standard in a 1989 ruling, and the department agreed in 1991 to award benefits to veterans with illnesses that were associated with exposure to Agent Orange, based on credible studies. The list now contains more than a dozen diseases.

    In the current case, the department argued that it was no longer required to pay retroactive benefits for any disease that was added to its list after September 2002, the expiration date of a federal law setting standards for Agent Orange payments.

    The appeals court disagreed, noting that Congress later extended the law through 2015 and said the department is still bound by the 1991 court order.