The Islamist militant responsible for spearheading the rampage that left several of Timbuktu’s ancient buildings and artifacts in ruins has pleaded guilty to his crimes.

According to The Atlantic, Ahmad al-Faqi al-Mahdi is the first Islamist rebel to stand trial at the International Criminal Court in The Hague. He’s also the first to plead guilty to the cultural destruction of the historic city of Timbuktu.

“I am really sorry, I am really remorseful, and I regret all the damage that my actions have caused,” Mahdi said following his guilty plea. “I would like to give a piece of advice to all Muslims in the world, not to get involved in the same acts I got involved in, because they are not going to lead to any good for humanity.”

Mahdi confessed to directing his fellow rebels to destroy nine mausoleums and a mosque door back in 2012 when Timbuktu was controlled by militants and members of al-Qaida in the Islamic Maghreb, The Guardian reports. During this time, Mahdi was allegedly a member of Ansar Eddine, a Tuareg movement with ties to the terrorist organization.

Once a city of learning and enlightenment, Timbuktu was overrun and ravaged by al-Qaida in 2012. The Guardian states that the rebels imposed sharia law, outlawed music and whipped people who refused to abide by their code. Mahdi was one of many leaders who had a hand in toppling several mud structures that served as sacred tombs and mausoleums.

The tombs were the “embodiment of Malian history captured in tangible form from an era long gone,” according to Fatou Bensouda, the court’s chief prosecutor. “He [Mahdi] was fully aware of the importance of the mausoleums, and he showed determination and focus in his supervision of operations.”

A number of other Timbuktu artifacts were destroyed as well, including priceless scientific manuscripts dating back to medieval times, shrines, valuable literature and artwork.

According to Atlanta Black Star, Islamist rebels who fled the historic city in 2013 set fire to the Ahmed Baba Institute, which housed an estimated 30,000 manuscripts. Documents on astronomy, medicine and mathematics, among other subjects, were destroyed in the blaze but served as an indicator that science was well underway in Africa before European settlers arrived, ABS reports.

“Our cultural heritage is not a luxury good – we must protect it from desecration and ravages,” Bensouda told the ICC. “This must be stopped in its tracks. History will not be generous to our failure to care.”

According to The Guardian, Mahdi faced up to 30 years in prison for his crimes but was able to strike a deal with the prosecutor’s office for a sentence of nine to 11 years. It’s hoped that Mahdi’s trial will serve as a precedent for other nations to prosecute crimes of cultural destruction.

Bensouda compared Mahdi’s case to the demolition of historic buildings and artifacts in Syria and Iraq last year. However, the ICC doesn’t have jurisdiction in those countries to bring charges against the perpetrators, the Washington Post reports.

Bensouda said she’s looking to bring additional charges against Mahdi.

“We are also investigating other crimes,” she said. “So this is the first case we’ve brought and we will see with respect to other crimes that have been committed within the context in Mali.”

The accused Islamist rebel has since taken full responsibility for his actions.

“All the charges brought against me are accurate and correct,” Mahdi said.