Georgia\'s leader on Wednesday deployed police in jails to replace prison officers after videos showing the alleged rape and beatings of convicts sparked protests ahead of bitterly-contested elections. \"Patrol police must immediately enter all prisons,\" President Mikheil Saakashvili said on Georgian television, demanding a complete overhaul of the ex-Soviet state\'s much-criticised jails as he announced the emergency measure. \"There must be zero tolerance towards rights abuses,\" Saakashvili said. The country\'s prisons minister has already resigned over the scandal and the government promised to eradicate the \"torture\" of convicts. \"We guarantee that we will eradicate torture in the penitentiary system,\" Prime Minister Vano Merabishvili said in a televised statement. Some of the graphic video footage, aired late Tuesday by opposition television station TV9, showed a weeping half-naked male prisoner at a jail in Tbilisi begging for mercy before apparently being raped with a stick. Another video released by the interior ministry showed prison guards brutally kicking an inmate. \"What happened in penitentiary number 8 is horrific and I have submitted my resignation to the prime minister,\" prisons minister Khatuna Kalmakhelidze said on television. A government statement said that 15 alleged perpetrators had already been arrested and claimed that the videos were staged by provocateurs paid to discredit the authorities ahead of the polls. \"It should be noted that these were premeditated crimes and there is evidence that those who arranged, conducted and recorded these abuses were paid to do so,\" the government statement said. The videos have caused a scandal ahead of the October 1 polls which will see Saakashvili\'s ruling party facing a major challenge from an opposition bloc led by billionaire tycoon Bidzina Ivanishvili, who has vowed to oust the government.  Several hundred people staged an angry protest and blocked one of the capital\'s main streets, some carrying hand-drawn pictures of prisoners being beaten and others holding photographs of relatives allegedly abused in jails. \"I am protesting against torture in prisons, which are under the strict control of the authorities. The authorities are responsible for what\'s happening there,\" one demonstrator, bank worker Mikheil Javakhishvili, told AFP. \"All of Georgia must take to the streets in protest against this horror,\" said another protester, Sophia Gabichvadze. The rally\'s organisers demanded an independent investigation and the resignation of more senior ministers. Small protests were also held outside the prison in the Tbilisi suburb of Gldani where the alleged abuse took place and in several other Georgian towns, according to local media. The interior ministry said in a statement that the alleged abusers were prison officers who \"exercised inhumane treatment against prisoners and made video records according to a previously elaborated plot\". One of the videos purports to show an inmate tied to the bars of a cell with what appears to be a stick inserted in his anus. A voice repeatedly asks him: \"What are you?\" The alleged convict replies that he is a crime boss. Next month\'s electoral battle promises to be the toughest since Saakashvili\'s party came to power after the 2003 Rose Revolution, against a revitalised opposition led by tycoon Ivanishvili whose TV station aired some of the prison videos. Tensions have escalated, raising fears of confrontation in the small Western-backed Caucasus republic with a recent history of political unrest.