The International Criminal Court prosecutor issued a renewed appeal Friday to Libyan authorities to arrest a Libyan commander wanted by the court for war crimes, after he was linked to a shocking video purported to show brutal killings.

Prosecutor Fatou Bensouda said in a statement that she is deeply concerned by a twin car bombing in Benghazi that killed at least 34 people this week and that she is “equally appalled” by images purportedly showing commander Mahmoud al-Warfalli killing 10 people “in what appears to constitute retaliation” near the site of the bombings.

In a video that went viral on social media, the shooter, a man in military uniform, is seen standing before 10 blindfolded people in blue jumpsuits who are on their knees, hands tied behind their backs. He then opens fire with a machine gun, shooting each man in the head.

Human Rights Watch and Amnesty International said the shooter appears to be Al-Warfalli.

The United Nations Security Council called on the court to begin investigating atrocities in Libya in 2011 as former ruler Moammar Gadhafi violently cracked down on protests against his regime. But the court still has yet to take custody of any suspect from the lawless country.

The court issued an arrest warrant for al-Warfalli in August 2017 on suspicion of involvement in the killings of 33 people in 2016 and 2017.

“I am dismayed that Mr. Al-Werfalli appears to remain in a position of command, and allegedly continues to commit crimes with impunity, despite an official statement from the General Command of the Libyan National Army in August 2017 that Mr. Al-Werfalli had been arrested and was under investigation by a military prosecutor,” Bensouda said.

She appealed to the chief of the Libyan National Army, Gen. Khalifa Haftar, “to heed my previous call to the LNA to work with the Libyan authorities to enable the suspect’s immediate arrest and surrender to the ICC.”

Bensouda said the “appalling cycle of violence and impunity in Libya cannot be allowed to continue for the sake of the Libyan people and the security and stability of the country and the region.”