Zimbabwe's public sector doctors went on strike on Tuesday, demanding a further salary increase of 401 percent that they want indexed to the US dollar despite accepting an earlier offer from the government of a 60 percent pay rise. Zimbabwe is mired in its worst economic crisis in a decade, with triple-digit inflation, rolling power cuts and shortages of US dollars, fuel and bread that have revived memories of the hyperinflation that forced it to ditch its currency in 2009. President Emmerson Mnangagwa's government has proposed big pay rises for doctors and other public sector workers in an attempt to avert crippling strikes. Police have banned a series of protests called by the opposition in major cities and have used tear gas and water cannon to disperse demonstrators. The main unions representing doctors and teachers, who make up the bulk of public service workers, said they had rejected the government's salary offers, which would see the lowest paid worker earning 1,023 Zimbabwe dollars ($90.45) a month. The doctors accepted their 60 percent pay increase but said it was not sufficient to avert planned strike action. The teachers are not currently on strike. "We met with the government representatives yesterday and they promised to expedite other allowances for health personnel but so far it has just been empty promises," the head of the Zimbabwe Hospital Doctors Association (ZHDA), Peter Magombeyi, said. "They have taken us for granted for too long, but we are ready to go back to work as soon as they offer us something tangible, which has not been forthcoming so far." The Health Services Board (HSB), which represents the government, said in a statement late on Monday that it was surprised the doctors were taking strike action despite accepting the earlier pay offer. ZHDA wants wages, which were previously pegged to the US dollar, to be paid at the prevailing inter-bank market rate and says its members can no longer afford to report for duty due to surging inflation and the deterioration in the economy. Their current salaries are worth less than 10 percent of what they were before the peg was scrapped due to high inflation. At 1030 GMT on Tuesday, the Zimbabwe dollar traded at 11.31 against the US dollar in the interbank market and 12.5 in the black market. Both rates are used to buy goods. — Reuters