CHICAGO (CBS) — Abortion rights activists have covered up the billboards mounted on the side of a South Side building, which use President Barack Obama’s image in an anti-abortion message.

The three billboards, mounted on the side of a building at 5812 S. State St., show an artistic rendering of Obama in profile, with a message alongside the picture reading, “Every 21 minutes, our next possible leader is aborted.” They are among more than 30 planned billboards paid for by the Texas-based group Life Always.

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On Sunday, cloth banners covered two of the billboards – one reading, “In 21 minutes, this sign should be gone,” the other reading, “Abort racism.”

A group of social workers and community members claimed responsibility, the Chicago Tribune reported.

When the billboards were unveiled last week, Life Always said the purpose of the campaign was “to encourage reflection on the disproportionate number of abortions among African American, who comprise less than 13 percent of the population and about 36 percent of the country’s abortions.”

In a statement on the group’s Web site, Life Always Board Member the Rev. Derek McCoy says, “These are babies who could grow to be the future President, or the next Oprah Winfrey, Denzel Washington or Maya Angelou.”

Some opponents wanted the billboards taken down immediately.

The group Black Women for Reproductive Justice calls the billboards “offensive to black women and the black community overall.” The group says it saw workers “cowardly” mounting the billboards in the dark overnight, and finds the message infuriating.

“These billboards are painting an abhorrent image of Black women as perpetrators of a plan to eradicate the future Black race,” Black Women for Reproductive Justice president and chief executive officer Toni Bond Leonard said in a news release. “That they would place these billboards in the Black community with such a despicable lie is reprehensible.”

Life Always has already caused a stir with the messages on its billboards. Last month, a three-story high billboard was mounted on the side of a building in the SoHo section of New York City, reading, “The most dangerous place for an African-American woman is in the womb.”

The New York billboard was taken down amid protests.