Burundi is East Africa's most corrupt country for the second year in a row, with the region's police, revenue authorities and the judiciary rated as the worst offenders, a Transparency International (TI)survey showed on Friday. Rwanda was ranked least corrupt in the five-member East African Community trade bloc, said the TI survey, released on Thursday. Burundi had a bribery prevalence rate of 37.9 percent, from 36.7 percent in 2010, while Uganda had a rate of 33.9 percent from 33 percent last year. Tanzania's bribery rate rose to 31.6 percent from 28.6 percent previously. Kenya, whose anti-corruption body is investigating a number of high profile graft cases, recorded a bribery prevalence of 28.8 percent, down from 31.9 percent. Rwanda fell to 5.1 percent from 6.6 percent in 2010. "The police, revenue authorities and the judiciary across the different countries were poorly rated in the regional aggregate index," TI said. Police in Kenya, Uganda, Tanzania and Burundi appeared on the list of the ten most bribery-prone institutions in East Africa, it added. The trade bloc is trying to market the five member countries jointly to potential investors. Graft is among the main concerns that businesses cite as a hurdle when setting up shop. "The commitment shown by the East African countries to attract foreign investments and promote trade in the region may face challenges if corruption and other forms of public inefficiencies are not tackled," Transparency said. "Improving governance practices therefore becomes an urgent imperative if the East African countries are to achieve developmental objectives," it said. "Confronting corruption occupies the core of such a response."