The African Union called the terrorist attack at the Bardo Museum in Tunisia’s capital "heinous and cowardly," and said the attack also underlined the need for greater cooperation among African nations to fight the scourge of terrorism and violent extremism. Nkosazana Dlamini-Zuma, the chairperson of the commission of the African Union, strongly condemned the attack, which left at least 23 people dead Wednesday, including the two gunmen. Zuma also added the attack “illustrates once again the need for renewed efforts to strengthen inter-African cooperation in the fight against terrorism and violent extremism,” according to a press release from the African Union.

Five gunmen stormed the Bardo Museum in Tunis Wednesday, killing dozens of people – mostly foreign tourists. Tunisian Prime Minister Habib Essid revealed the names of two attackers who were killed during the raid, Yassine Laabidi and Hatem Khachnaoui. The former had earlier been flagged by the country’s intelligence services, Essid reportedly said in an interview with France’s RTL radio Thursday. The remaining three attackers have not yet been identified and are still at large.

The attack in Africa’s northernmost country follows a decision by the African Union, a 54-member continental bloc, to deploy 7,500 troops to combat the Boko Haram insurgency in Nigeria. During a Peace and Security Council meeting earlier this month, Dlamini-Zuma said the force had yet to yield tangible results. “I am deeply concerned by the prevailing situation on the ground,” she said. “Since the last meeting of Council, attacks by the Boko Haram terrorist group have continued unabated, both in Nigeria and in the neighboring countries, causing further killings, destruction and suffering.”

Boko Haram has declared an Islamic caliphate that now encompasses about 130 towns and villages in northeastern Nigeria. The terror group has been a longtime supporter of the Islamic State group and recently began publishing its own reports of attacks which resemble ISIS’ brutal style, including a video purporting to show the beheading of two men accused of spying. Earlier this month, Boko Haram pledged alliance to the militant group based in Iraq and Syria. ISIS officially accepted the pledge last week.

It is not yet known if Laabidi and Khachnaoui were linked to a particular terrorist group, and no group has so far claimed responsibility for the attack. But the raid came just two days after social media accounts affiliated with the Islamic State group claimed that a planned attack on Tunisia was imminent