JERUSALEM, Jan. 8 (JTA) — Israel’s election campaign broadcasts began this week, but the real battle for public opinion was dominated by new corruption allegations involving Prime Minister Ariel Sharon. Already facing a loss of support over allegations of vote-buying and corruption in November’s Likud Party primaries, Sharon took another blow with the latest disclosure involving himself and his sons, Omri and Gilad. The Israeli daily Ha’aretz reported Tuesday that an investigation of alleged bribery, fraud and breach of trust had been launched surrounding a $1.5 million loan Sharon’s sons took from Cyril Kern, a family friend in South Africa. According to the report, Gilad and Omri Sharon received the money from Kern as collateral for a loan they took to pay back a company through which Sharon had received illegal campaign contributions in his 1999 bid for the Likud Party leadership. Among the allegations was whether Sharon misled police when he told them in April 2002 that the contributions, repaid at the order of the State Comptroller, were paid back through a mortgage on his Negev ranch. In fact, the mortgage offer initially was accepted but later was rejected for legal reasons, Ha’aretz reported. The contributions ultimately were paid back because of the low-interest loan from Kern, the paper wrote. On Wednesday, Sharon denied any improprieties surrounding the loan, calling the allegations “a despicable political plot, which I will disprove with documents and facts.” The allegations, he said, have “one single goal — to bring about the downfall of the prime minister.” A day earlier, Sharon political adviser Eyal Arad told a news conference that the loan had been paid back, along with interest and taxes, with full disclosure to the relevant authorities. Attorney General Elyakim Rubinstein voiced outrage Wednesday that word of the investigation had been leaked to the media. Interviewed on Israel Radio, Rubinstein said all material regarding the case had been marked classified, but had been leaked by someone with political motivations. “Whoever released this material at this time did not release it in order to help expose the truth. He did it because of the timing,” Rubinstein said, referring to national elections scheduled for Jan. 28. Rubinstein added that it was unlikely the investigation would be completed before the election. He said a request for information had been submitted to South African authorities, which would delay the investigation. Kern came to the prime minister’s defense Wednesday, calling the leak “character assassination.” Kern, originally from England, told JTA he had moved to South Africa six years ago. He is not well known in the Cape Town Jewish community. Kern said he met Sharon when they served together in Israel’s 1948 War of Independence. Kern had gone to volunteer for the fledgling Israel Defense Force. Meanwhile, Sharon’s main political rival, Labor Party leader Amram Mitzna, called on Sharon to explain the events or resign.