A group of armed Libyan civilians concerned about the potential of their country’s rich ancient heritage are patrolling Leptis Magna, an ancient city of Rome. They fear the Islamic State will do in Libya what it has done in Iraq and Syria: defaced and destroyed some of the richest and most important artifacts and buildings in world history.This article summarizes a number of media reports and gives some background on the city. And there is additional information in this AP article: Unlikely saviors of Libya's Roman remains.
Though the city of Leptis Magna is in ruins now, some fine architecture and art remain. There are only around 20 citizens armed with Kalashnikov rifles surrounding Leptis Magna and the surrounding archaeological ruins, which covers an area of about 120 acres (50 hectares).
Leptis Magna has come up a couple of times at PaleoJudaica (here and here).