WASHINGTON (AP) _ The head of the U.S. Public Health Service is being accused of ''medical terrorism'' for not allowing more sufferers of AIDS, cancer, multiple sclerosis and glaucoma to be legally treated with marijuana.

Ten Americans receiving government-supplied marijuana asked James O. Mason on Tuesday to resign from his job over his refusal to send the drug to 30 other patients whose applications for marijuana treatment have been approved by the Food and Drug Administration.

''You are engaged in a calculated campaign of medical terrorism directed against desperately ill people,'' they wrote to Mason, who also is the Department of Health and Human Services' assistant secretary for health.

''Your actions are not merely illegal, they are immoral'' and have caused '''much unnecessary human suffering,'' said the letter, which was organized by the Washington-based Alliance for Cannabis Therapeutics.

Mason last week received another angry letter on the medical marijuana issue from fellow administration official Ingrid A.C. Kolb, the Office of National Drug Control Policy's acting deputy director for demand reduction.

Kolb described HHS's behavior in the matter as ''unconscionable'' and showing ''an intolerable lack of compassion.''

Publicly, Mason has said nothing about either letter, according to Rayford Kytle, a Public Health Service spokesman.

Mason announced last June that HHS would stop processing new applications for medical marijuana treatment until it finished a review of the drug's reported health benefits and potential dangers.

That review has been completed and Mason has sent his recommendation to HHS Secretary Louis Sullivan, said Kytle, who would not discuss the contents of the recommendation.

Sullivan is ''aware that this is a heated issue ... and it's something we need to do something about quickly,'' Kytle said.

Advocates of using marijuana as a medical treatment say it combats nausea, vomiting and weight loss common to cancer patients undergoing chemotherapy and to some AIDS sufferers. They claim it also is effective in easing eye pressure in the treatment of glaucoma and reducing muscle spasms common to such neurological conditions as multiple sclerosis.

Opponents contend that marijuana's medical value is unproven and that synthetic drugs exist for addressing the same problems. In addition, they say marijuana could have harmful side effects, particularly to those with immune deficiencies, and that the government acting as a supplier of it while conducting a war on drugs sends the wrong signal.

Alternative drugs touted by the government include Marinol, a pill with some of marijuana's chemical attributes, and Zofran, an intravenous medication.

Mason said last June that marijuana would still be supplied to those already getting it and for the approved applicants. But then he denied the marijuana deliveries to the 30 approved applicants, Kytle said.