Sudanese rebels said Sunday they attacked two military bases in war-torn Blue Nile state, days after attending a round of peace talks with the government.

The Sudan Peoples Liberation Army-North raided the bases in Blue Nile last week "in retaliation for the aerial bombardment" of two towns, SPLA-N spokesman Arnu Lodi said in a statement.

Fighting flared in the state last month after the end of the rainy season, which leaves many roads impassable, despite both sides meeting at peace talks in Ethiopia until last week.

Lodi said SPLA-N forces attacked a military camp in the town of Buk in central Blue Nile on Tuesday "and managed to destroy one mounted land cruiser".

The rebels launched another raid on a base 30 kilometres (18 miles) from state capital Ed Damazin on Saturday, killing four soldiers, Lodi said.

In the second raid, one rebel was wounded and another captured, he said on Facebook.

The insurgents launched the attacks in retaliation for government air raids on Chali and Yabus in southern Blue Nile.

But Sudanese Armed Forces spokesman Colonel Al-Sawarmy Khaled Saad told AFP the rebel claims were "completely untrue".

He said government forces had launched a ground attack on rebels as they massed troops in Yabus, in the far south of the state.

Saad gave no indication of casualties.

The unrest came after delegations from the government and rebels from South Kordofan and Blue Nile ended peace talks in Addis Ababa on November 18, with mediators saying they were "not too far from a deal".

Fighting erupted in Blue Nile and South Kordofan in 2011 when former rebels from the SPLA-N took up arms against Khartoum.

The insurgents complained of neglect and discrimination by Sudan's Arab-dominated regime.