A suburb of the US capital dedicated a monument Friday to World War II sex slaves in the latest local victory by Korean Americans in historical disputes with Japan.

After a campaign and fundraising by Korean American activists, the government center of Fairfax County, Virginia, unveiled twin sculptures of butterflies and a plaque in honor of so-called "comfort women" -- the up to 200,000 women from Korea and elsewhere forced into brothels for imperial Japan's soldiers.

On a green knoll on the government building's sprawling lawn, supporters released butterflies and sang the Korean folk anthem "Arirang."

A dancer in Korean costume cried as she glided around the plaque, which calls for "eternal peace and justice" for comfort women.

The Fairfax County Board of Supervisors, in a proclamation, said the monument "will serve as a lasting reminder and an affirmation to the world that all crimes against humanity, such as human trafficking, will not be condoned or tolerated."

Former comfort woman Kang Il-Chul, 87, flew in from South Korea to thank the crowd, saying she would share news of the monument to the dwindling number of remaining survivors.

"The Japanese government should make a prompt apology for the comfort woman issue," Kang said.

Japan apologized to comfort women in 1993 and set up a fund to compensate survivors.

While comfort women in the Philippines and elsewhere accepted the money, most South Koreans refused because the funds came primarily from private sources and not the Japanese government.

Japan's embassy in Washington said that Prime Minister Shinzo Abe stood by Tokyo's "sincere apologies and remorse" for comfort women's "immeasurable pain and suffering" and did not want the issue to be "politicized."

Abe has said he will not revise the apology, after in the past triggering concern in South Korea over his conservative views on wartime history.

Some Japanese politicians have rejected the official line on comfort women and accused South Korea and China of keeping alive historical grievances for political gain.

Korean American activists have increasingly taken the battle over history-linked disputes to the local level in the United States.

State lawmakers in Virginia, which has a sizable Korean American community, in February voted to include the Korean term "East Sea" in textbooks for the body of water more frequently called the Sea of Japan. (AFP)