Militias from the Libyan city of Misrata are "terrorising" displaced residents of the town of Tawargha over their alleged loyalty to Muammar Gaddafi, says a rights group. The entire town, once home to 30,000 people, has been abandoned, said US-based Human Rights Watch (HRW). Parts have been ransacked and burnt and residents told not to return, it said. The ruling NTC said it has ordered its forces not to loot and that an inquiry would be held in case of wrongdoing. "We are in complete harmony. If there has been anything outside the law, there will be an investigation," said Deputy Defence Minister Fawzi Abu Katif. HRW said it had reports of militiamen shooting unarmed Tawarghans and of arbitrary arrests and beatings, some of them leading to deaths, HRW said. The militias are accusing the Gaddafi loyalists in Tawargha of committing atrocities, such as murder and rape, alongside Gaddafi forces in Misrata. The majority of the town's residents are non-Arab Libyans, many of them descendants of African slaves. "Revenge against the people from Tawargha, whatever the accusations against them, undermines the goal of the Libyan revolution," said Sarah Leah Whitson, HRW's Middle East and North Africa director. "In the new Libya, Tawarghans accused of wrongdoing should be prosecuted based on the law, not subject to vigilante justice," she added. HRW says its conclusions were based on the testimonies of dozens of people across the country. Pro-Gaddafi forces used Tawargha as a base for attacks on Misrata when they besieged the city during the Libyan uprising. The anti-Gaddafi militia fought their way out and began an advance on the Libyan capital, Tripoli, back in August.