Shrieking protesters at the AIDS conference in Spain drowned out U.S. health secretary Tommy Thompson as he attempted to speak about American global AIDS programs on Tuesday.

About 40 people who demanded more U.S. funding clambered onto the lecture platform as Thompson tried to address the 14th International AIDS Conference; some waved placards declaring "Wanted: Bush and Thompson for murder and neglect of people with AIDS."

As security officers protected the secretary, protesters shouting "Shame! Shame!" blocked him from view of the lecture audience and created such a din that he could not be heard.

Thompson then left the platform and held a news conference behind the auditorium.

"The United States is passionately committed to this international fight," the head of the Department of Health and Human Services calmly told reporters.

"I understand that people are passionate about this and want to blame the United States," Thompson said. "But the United States under President Bush has doubled the amount of resources it provides for the fight against AIDS."

Last month, Bush announced a five-year, $500 million initiative to stem transmission of HIV from mother to child in Africa and the Caribbean. More than 2 million women carrying the AIDS virus give birth each year, and 90 percent of those pass it on to their young during pregnancy, childbirth or nursing.

Critics called the proposal "grossly underfinanced."

AIDS activists complain that Bush is ignoring people already living with the disease. They want the United States to contribute more to the U.N.-backed Global Fund to Fight AIDS, Tuberculosis and Malaria. The United States has pledged $500 million to that fund.

"I understand that people want to yell and scream," Thompson said, "but they would serve their cause much better ... if they would help other countries see the light."

"They can shout, but that doesn't deter me or the president one bit," he said.