Secretary of State Hillary Rodham Clinton decried the enslavement of up to 27 million people around the world as her department released its annual report on human trafficking Tuesday.

She cited progress in 29 countries and honored 10 "heroes" who have battled the problem from Argentina to Cambodia to Mauritania, but she reserved her most emotional comments for the global problem she has witnessed firsthand for 17 years.

Last month in Kolkata, India, Clinton was moved to see young women freed from the sex trade perform dance routines and karate moves. She recalled Tuesday one young girl's "pride and accomplishment" and said she still sees the girl "in my mind's eye, in the years and decades ahead."

"We're still struggling to make it a mainstream issue, which is taking a long time," Clinton said in India.

Tuesday, she was only slightly more upbeat. "These victims of modern slavery ... their stories remind us of what kind of inhumane treatment we are still capable of as human beings," she said. "Traffickers prey on the hopes and dreams of those seeking a better life, and our goal should be to put those hopes and dreams back within reach."

The report, released by Luis CdeBaca, the State Department's ambassador-at-large to monitor and combat trafficking in persons, estimated that 21 million victims remain in slavery around the world. Some estimates go as high as 27 million, the figure Clinton cited.

More than half the victims are in India, China and Southeast Asia, the area Clinton visited last month. Most are enslaved by private employers, but millions work the sex trade or are in state-imposed forced labor.

By contrast, 42,000 victims were helped by their governments last year. Fewer than 8,000 prosecutions and fewer than 4,000 convictions resulted -- improvements from 2010, but a fraction of the overall problem.

Of the 186 countries rated in the report, only 33 were meeting standards for combating slavery, while 17 were totally non-compliant. Among the worst offenders: Cuba, Iran, North Korea, Libya, Saudi Arabia, Sudan and Syria.