Tamil Tiger rebels sank a navy ammunition ship moored in the northeast of Sri Lanka on Saturday with no casualties reported, and infantry clashes in the embattled north killed 24 rebels and two soldiers, the military said. The attacks coincide with key elections in the tense eastern province. The guerrillas said their Sea Tiger commandos managed to infiltrate the tightly guarded port of Trincomalee in the early hours. The navy said the “MV Invincible” sank after the underwater explosion but no lives were lost. The explosion came just hours after a bomb ripped through a crowded cafe in Ampara, also in the east, late on Friday, killing 12 people and wounding at least 36. Officials also blamed the LTTE for that attack. Despite the ongoing violence, voting was held on Saturday for the eastern provincial council that the government hopes will boost its fight against the ethnic rebels, who control a large part of the island's north. The polls are the first to be held in the eastern districts of Batticaloa, Trincomalee and Ampara in 20 years, and close to a million people are eligible to vote. The eastern region, once home to several LTTE enclaves, was brought under government control after heavy fighting last year and Colombo is determined to show normality has returned. “Turnout in Trincomalee and Ampara is around 50 percent each, and Batticaloa 30 percent. People are really frightened to go out and vote,” said the chairman of a rights group People's Action for Free and Fair Elections Kingsley Rodrigo. In the east, the president's ruling United People's Freedom Alliance has allied itself with the Tamil Makkal Viduthalai Pullikal (TMVP), or Tamil People's Liberation Tigers, a controversial militia comprised of LTTE defectors. The main opposition UNP, has teamed up with the biggest Muslim party, the SLMC. The election was also marred by claims of fraud and ballot stuffing carried out by ruling party supporters. The Sinhalese-dominated government of President Mahinda Rajapakse also says the election of a 35-member provincial council is proof it is willing to devolve some power to areas with large Tamil communities.