Armed gunmen attacked a civilian convoy including a passenger bus in central Mozambique early Saturday, killing one and wounding at least 10, a witness and hospital worker said.

It was the second attack this week after the former rebel movement Renamo on Monday declared that a 1992 peace deal was over after government forces took over their military base in central Mozambique's Gorongosa mountains.

Mozambique's former rebel movement Renamo said Friday one of its lawmakers was killed in a raid on its military base by government troops earlier in the week.

The statement came after Renamo, which fought a bloody civil war against the ruling Frelimo party before transforming into a political party, declared that a 1992 peace deal was over.

South Africa on Thursday said violent clashes in Mozambique were a serious concern, with stability in the neighboring country critical to the rest of the region.

A 21-year peace deal was declared over earlier this week by the former Renamo rebels who fought against the Frelimo-led government in the country's brutal civil war, amid a fresh spate of skirmishes with government troops.

The United States on Wednesday voiced concern at the political unrest in Mozambique, urging all sides to work together to overcome their differences.

The former Renamo rebels declared Tuesday that a 1992 peace deal is over, although they later reaffirmed that they do not want a return to war.

Mozambique's Renamo and the country's president are determined to avert a new war, despite the ex-rebels declaring a 1992 peace deal over, a negotiator said Tuesday.

Renamo demanded that government forces withdraw from the group's military base they seized on Monday, pledging not to restart hostilities, independent negotiator Lourenco do Rosario told a press conference after meeting the group's leaders.

Mozambique government forces on Thursday killed two fighters from rebel group Renamo in clashes on the first anniversary of their leader's return to the bush, the president's office said.

"Security forces were going about their normal work when they were surprised by a Renamo attack," presidential spokesman Edson Macuacua said late Thursday.

Mozambique's bid to end a conflict with former rebels that has unnerved investors hit an impasse on Wednesday after the group's leader refused to leave his bush camp for talks.

Former rebel leader Afonso Dhlakama has refused to leave his base in the Gorongosa Mountains to meet President Armando Guebuza, unless armed forces withdraw from the area.

South African President Jacob Zuma said Thursday that the condition of ailing anti-apartheid hero Nelson Mandela had improved overnight and was now critical but stable.

"He is much better today than he was when I saw him last night. The medical team continues to do a sterling job," Zuma said in a statement.

Global mining giants Vale and Rio Tinto have neglected thousands of Mozambicans who have been moved from mining areas and resettled without proper homes or income, Human Rights Watch alleged on Thursday.

"Many of the 1,429 households resettled to make way for Vale and Rio Tinto's international coal mining operations ... have faced serious disruptions in their access to food, water, and work," the rights group said.

Nine South African policemen told a court Friday they were not guilty of murdering a Mozambican immigrant who was dragged behind a police van and then brutally beaten to death.

The group are accused of killing Mido Macia, a 27-year-old taxi driver, who died in police custody on February 26 after being confronted for parking his taxi on the wrong side of the road.