A South Sudan rebel leader was killed Saturday just days after agreeing to a cease-fire in the region.

The South Sudan army and a rebel source in Unity state say Gatluak Gai was shot dead.

Gai signed a cease-fire agreement with the new South Sudan government last week.

There are conflicting reports on who is responsible for his death, ranging from Gai being shot by his own men, to being killed by South Sudan's army.

Gai headed one of several militias in what recently became the world's newest country, South Sudan.

In a call for peace, South Sudan President Salva Kiir announced an amnesty for militias that have fought the South Sudanese government in recent months.

Southern Sudan voted overwhelmingly to split from the north in a January referendum. The vote stemmed from the 2005 peace deal that ended the Sudanese civil war.