BENGHAZI, Libya (Reuters) - East Libyan forces said they had gained control on Saturday over one of two remaining districts of Benghazi where they faced armed resistance.

The advance in the central Souq al-Hout neighborhood was the latest step in the slow progress of the self-styled Libyan National Army commanded by Khalifa Haftar, which has been waging a campaign against Islamists and other opponents in Libya’s second city for more than three years.

In unusually heavy fighting in Benghazi over the past two days at least 13 men from the LNA were killed and 37 wounded, a medical official said. Many of those who died were killed by land mines, a military source said.

Along with Sabri, Souq al-Hout was one of the final holdouts of the LNA’s rivals.

Since 2014, shifting alliances have been battling for power. The LNA and an eastern-based government have rejected a U.N.-backed government that has been in the capital, Tripoli, since last year.

Saturday’s advance came after the Benghazi Defence Brigades (BDB), an anti-Haftar armed group that includes fighters who retreated from Benghazi and have since tried and failed to advance again toward the city, said it was prepared to disband and be integrated into national security forces.