A South Sudanese opposition member of parliament has been shot dead at his home in the country's capital, Juba.

Four gunmen stormed Luka Mathen Toupiny Luk's home in Gudele at 10 pm on Saturday and fatally shot the lawmaker, his spouse, Nyan Akolde, told Sudan's Post on Sunday. Gudele is located in Juba's west.

The legislator had arrived home from evening prayers, when the fatal attack occurred, Akolde said. Mathen was taken to hospital in critical condition, but succumbed to his injuries around one hour later, the widow added.

According to Akolde, two suspects have been arrested in connection with her husband's shooting, while another two remain at large.

Motive unknown

The motive behind Mathen's killing is yet to be known.

Mathen represented Cueibet county in the Council of States, South Sudan's upper house of the National Legislature. Cueibet is located in Lakes state in central South Sudan.

Mathen, a former court clerk, was appointed to the Council of States in 2018 following the signing of South Sudan's Revitalised Peace Agreement.

He joined the legislative house under the ticket of Other Political Parties (OPP), an opposition-aligned outfit.

Main opposition demands justice

The main opposition, SPLM-IO, under the leadership of suspended First Vice-President Riek Machar, has urged authorities to investigate Mathen's death and arraign his killers.

Mathen was known for his contribution in parliament's education committee and holding the national leadership to account, SPLM-IO lawmaker, Juol Nhomngek Daniel, told Sudan's Post on Sunday.

South Sudan's police service had not yet issued an official statement as of the time of publishing this story.