A proposal to rename a Brooklyn street after a black activist, Sonny Carson, made its way to City Hall with the support of a little-known group, the December 12 Movement.

A City Council staff member, Viola Plummer, who made a death threat against Council Member Leroy Comrie of Queens, is chairwoman of the organization, which has ties to the United Nations and the African Union. Carson, who died in 2002, was a member.

After Mr. Comrie abstained from a vote on the Carson street name, Ms. Plummer said: “If it takes an assassination,” he will not be president of Queens. Mr. Comrie is considered a likely candidate for the post.

Ms. Plummer said the December 12 Movement, named for a 1987 protest against police brutality in Newburgh, N.Y., is a human rights organization. It was the first to propose naming a stretch of Gates Avenue in Brooklyn after Carson, who described himself as “anti-white.”

Ms. Plummer said the organization combats torture, poverty, and human rights violations, and promotes economic and social justice.

The Zimbabwean government’s newspaper, the Herald, has written at length about the group and its support for President Mugabe, whom many international groups consider a despot responsible for widespread human rights abuses.

In April, Ms. Plummer delivered gloves, stethoscopes, surgical blades, and other medical supplies to the Zimbabwean minister of health and child welfare, the Herald reported. She said she wants to “dispel this idea of a political and economic crisis” in Zimbabwe.

The executive director of the New York Civil Rights Coalition, Michael Meyers, said the December 12 Movement is a radical fringe group.

“They are people living in the past,” he said. “Nobody takes them seriously. This group has been loose and full of racial rhetoric for years.”

Mr. Meyers said he does not consider Ms. Plummer’s comments a death threat.

“They are racial bullies. They try to intimidate,” he said. The “assassination” comment, he said, is ” something you have to laugh about.”