The United States on Wednesday unilaterally blacklisted Libya's Kaniyat militia and its leader loyal to putschist Gen. Khalifa Haftar which is allegedly behind multiple murders, kidnapping and torture.

The move comes after Russia last week prevented a U.N. Security Council (UNSC) committee from imposing sanctions over the group's human rights abuses.

The U.S. sanctions were imposed under the Global Magnitsky Act, which allows the U.S. government to target human rights violators worldwide by freezing assets and prohibiting Americans from doing business with them.

The Treasury Department blamed the pro-Haftar group for torture, forced disappearances and displacement of civilians in the conflict-hit country, Reuters reported.

"Mohamed al-Kani and the Kaniyat militia have tortured and killed civilians during a cruel campaign of oppression in Libya," U.S. Treasury Secretary Steven Mnuchin said in a statement and added that the group and its leader "are responsible for the murder of civilians recently discovered in numerous mass graves in Tarhuna."

Last month Libyan authorities dug up 12 bodies from four unmarked graves in Tarhuna, adding to the scores of corpses already discovered since June.

The Libyan city of Tarhuna, which was recaptured in June by the internationally recognized Government of National Accord (GNA), had for years been controlled by the Kaniyat militia run by the local al-Kani family, which fought alongside Haftar’s eastern-based illegitimate forces. Tarhuna was also the main staging point for Haftar's abortive offensive aimed at seizing the capital from the legitimate government.

Mnuchin vowed U.S. solidarity with Libyans, saying Washington "will use the tools and authorities at its disposal to target human rights abusers in Libya and across the world."

"In June 2020, following a de facto truce, GNA-aligned forces reentered Tarhuna and discovered at least 11 mass graves containing the bodies of civilians previously detained by the Kaniyat militia, including women, children, and elderly," the statement said. "Some of the deceased appeared to have been tortured, burned, or buried alive. The Kaniyat militia is also responsible for hundreds of summary executions at Tarhuna prison, numerous forced disappearances, and the displacement of entire families from Tarhuna," it added.

The U.S. and Germany earlier this month proposed that the UNSC's 15-member Libya sanctions committee impose an asset freeze and travel ban on the Kaniyat militia and al-Kani.

However, such a move has to be agreed by consensus, and Russia said on Friday it could not approve the sanctions because it wanted to see more evidence first that they had killed civilians.

Last month the two major sides in the country's war agreed to a cease-fire. Turkey backs the GNA. Russia, the United Arab Emirates (UAE) and Egypt support Haftar forces.