In response, Roger II sent Christodulus and George of Antioch on an expedition to Mahdia in July 1123.

What remained of this force attacked Pantelleria, with the island being pillaged and its inhabitants either massacred or enslaved.

However, the Zirid leader, Abu'l-Hasan al-Hasan ibn Ali roused his people into a holy war against the Normans, and two days later, they marched towards the fort of El-Dimas at night.

However, due to bad weather and the efforts of the Zirids, the Normans were unable to land and sailed back home.

The Normans launched a sortie against the Muslims, however, they were defeated and slain to the last man after a siege of 16 days that ended on August 9.