Zimbabwean police have arrested opposition leader Morgan Tsvangirai for the second time this week, preventing him from attending a campaign rally for the upcoming presidential run-off vote on June 27. The opposition Movement for Democratic Change has accused President Robert Mugabe of trying to hinder Tsvangirai's campaign in order to maintain his long-standing grip on power. Tsvangirai was later released from custody in Esigodini, located 40 km southeast of Bulawayo, after being stopped by armed police at a roadblock. The opposition party criticized Tsvangirai's detention as a desperate and disgraceful act by the regime, urging authorities to allow him to fulfill the mandate given to him by the people of Zimbabwe to restore their dignity. The police have banned several planned campaign rallies due to concerns over the safety of party leaders. The party has stated that they will take legal action to prevent police interference in the campaign. The police spokesperson blamed the opposition for a recent incident where the MDC convoy crashed through a roadblock. Tsvangirai, who won the March 29 election but did not secure enough votes to avoid a second ballot, was detained and questioned by police for eight hours. Diplomats from the U.S. and Britain were also stopped and held by police after visiting victims of political violence. Relief agencies have been barred from operating in Zimbabwe, exacerbating the country's economic crisis. U.S. Ambassador James McGee, who was one of those detained on Thursday, accused the government on Friday of using food aid as a way to gain votes. He described the regime as desperate and willing to do anything to maintain power during a video conference call from Harare. Washington has placed the blame for the diplomats' detention squarely on Mugabe's government. The United States and Britain, Zimbabwe's former colonial power, believe that Zimbabwe is attempting to intimidate Tsvangirai's supporters. France's foreign ministry expressed deep concern about the intimidation and violence taking place in Zimbabwe. The opposition claims that 65 people have been killed in violent incidents since the first round of voting. Mugabe is blaming his opponents for the unrest. Mugabe's government halted the operations of all international aid agencies in the country, accusing some of supporting the opposition. Britain and the European Union have called for the ban to be lifted. U.N. officials expressed concern that the suspension of aid would lead to increased suffering, while CARE stated that millions of aid-dependent Zimbabweans were in danger. EU aid commissioner Louis Michel expressed deep distress over the uncertainty faced by hundreds of thousands of people who rely on aid for survival. Zimbabwe, previously a prosperous country in Africa, has experienced a decline in food production since 2000 due to the government's seizure of white-owned farms for redistribution to poor blacks. This has led to chronic food shortages, forcing the country to rely on handouts and imports to feed its population. Mugabe attributes the decline of Zimbabwe's once thriving economy to sanctions imposed by Western nations, while the opposition believes he is responsible for the country's downfall due to mismanagement. The Southern African Development Community, which includes Zimbabwe, is dispatching observers to oversee the upcoming run-off election.