Maputo - Six people have been killed in an attack by Renamo rebels in Mozambique, police said on Monday, the latest in a string of violent skirmishes between opposition fighters and government forces.Two unidentified survivors claimed that government troops had staged the attack, but police laid the blame squarely on rebels."Armed men from Renamo ambushed a vehicle on Friday, firing at it until it caught fire," police spokesperson Daniel Macuacua told AFP."Six people were burnt to death." All the victims were civilians, though their identities have not been released."We are still looking for any potential survivors who may have escaped," Macuacua added.'Lined up and shot' But two survivors told the country's independent television channel STV on condition of anonymity, that the government troops were behind the attack.One claimed police stopped them, checked their identities and drove them into the forest. They were eight farm produce sellers, two of them Bangladeshis."They put the Mozambicans in a line and shot them down one by one. Then I was grabbed by the coat but I managed to get out of it and escaped (unharmed)," said the survivor, of Bangladesh origin.The second survivor said they were taken out to the bush where they were shot "one by and one" as they stepped out of the car.The man also a Bangladesh, claimed that he jumped out of car, was shot but "hid in the bush," he told STV from a local hospital.Renamo, which waged a 16-year civil war that ended in 1992, has refused to accept the results of 2014 elections when it was beaten once more by the ruling Frelimo party, in power since independence 40 years ago.Since 2013, tensions have risen and Renamo fighters have again taken up arms in a battle that it says is against a Frelimo elite who have enriched themselves at the expense of the country.Uptick in violence Peace talks are under way, but authorities blame the stand-off for an uptick in violent attacks in northern and central parts of Mozambique.In May, 13 bodies were found in the restive centre of the country where security forces and Renamo rebels have frequently clashed, while the Mozambican Human Rights League (LDH) claimed at least 83 summary executions had been reported since the start of the year.Renamo leader Afonso Dhlakama has been living in hiding since October 2015 after he escaped two attacks against his convoy.He claims government troops are continuously attacking his stronghold in Gorongosa in central Mozambique, in an attempt to lure him out or kill him.The clashes have intensified in recent months following Dhlakama's declaration in December that he would take power in six of Mozambique's 11 provinces which he claims he won in the 2014 elections.