THE HAGUE, Netherlands — The head of an international court that investigates war crimes and genocide renewed her call Wednesday for the arrest of a Libyan military officer alleged to have been involved in the killing of 33 captives “in cold blood.”

International Criminal Court Prosecutor Fatou Bensouda issued the call amid conflicting reports over whether Mahmoud al-Werfalli has been arrested. The court issued an arrest warrant for him in August.

Al-Werfalli is suspected of being behind a string of killings earlier this year in the city of Benghazi. Victims’ bodies were found in garbage dumps with bound hands and gunshots to the head.

Al-Werfalli “stands accused of serious crimes. I therefore again call on Libya to take all possible steps to immediately arrest and surrender him to the ICC,” Bensouda said.

The appeal underscores the problems faced by the court — which has no police force of its own to arrest suspects — in getting custody of suspects in conflict-torn Libya.

The court has filed charges against five Libyans, including former dictator Moammar Gadhafi, but none of them has been arrested and sent to The Hague to face justice. Gadhafi was captured and killed by rebels in 2011. His son Seif al-Islam is wanted by the court.

Libya sank into chaos following the 2011 uprising that toppled Gadhafi. Today it is split between rival parliaments and governments in the east and west, each backed by a set of militias, tribes and political factions.

Al-Werfalli heads an anti-terrorism unit under Field Marshal Khalifa Hifter, who commands a self-styled national army that is battling Islamic militants in the east. Hifter is allied with a government based in the east and is supported by Egypt, the United Arab Emirates and Russia.

Bensouda said that following publication of the warrant for Al-Werfalli in August the Libyan National Army announced he had been arrested. However, Bensouda added that she also has received reports that he remains at large “and may have been involved in additional killings since the ICC warrant of arrest was issued.”