JUBA, May 14 (Xinhua) -- South Sudan on Monday said its army killed 14 rebel fighters loyal to ex-army chief General Paul Malong following fighting last week in the Western Bhar el Ghazal region located northwest of the capital.

The South Sudan army (SPLA) spokesman Brig. Lul Ruai Koang, told Xinhua they clashed with a joint rebel force loyal to both Malong and the Sudan People's Liberation Army-in opposition (SPLA-IO) loyal to Machar at Birat near the border with Sudan, Dulu and Mangayat leaving 14 rebels dead including a senior rebel officer.

Koang said among the rebels killed included Brigadier Abdul Musa during the fight for control of Dulu area in Western Bhar el Ghazal which remains under government troops.

He said that the fighting happened after their position came under attack more than twice from May 9 at Birat and then on May 11 when Malong's forces joined hands with SPLA-IO to march to Belloku Southwest of Raja area.

He also revealed that the rebels after being defeated tried to take control of the Dulu area within the same region but were later on repulsed and the SPLA remains in control of the area.

"They tried to infiltrate the town of Dulu but were pushed out and 14 rebels in total were killed including Brig. Abdul Musa. We captured lots of AK47 rifles," Koang said.

The army spokesman said it marked the first time Malong's group was launching an attack on the government troops.

Former SPLA Chief of Staff Malong was sacked last year and formed the South Sudan United Front (SS-UF) to topple President Salva Kiir.

Meanwhile, Lam Paul Gabriel the SPLA-IO deputy spokesman said in a statement that they killed 28 government soldiers and that several civilians are displaced in the wake of fighting at Dulu.

"The regime's forces and JEM militias attacked the SPLA-IO base in Dulu but the SPLA- IO forces fought with zeal and bravery for four hours, killing 28 enemy soldiers and several others injured; while the SPLA IO lost one freedom fighter in the process. This fight caused more displacement to civilians as the regime's forces took the fight to the IDP area in Dulu," he said.

He also added that government troops are moving to attack Bazia area which is under their control.

"The SPLA -IO would like to alert Ceasefire Transitional Security Arrangement Monitoring Mechanism (CTSAMM) and IGAD that if these provocative movements lead to any hostile confrontation, the regime is to be held accountable," he said.

The clashes come as the government and opposition groups prepare to hold third round of talks on May 17 in the Ethiopian capital.

South Sudan descended into violence in December 2013 after political dispute between President Kiir and his former deputy Riek Machar led to split within the SPLA, leaving soldiers to fight alongside ethnic lines.

The 2015 peace agreement to end the conflict was weakened after the outbreak of renewed fighting in July 2016.