DAR ES SALAAM (Reuters) - An opposition presidential candidate in Zanzibar detained as he tried to vote early on Tuesday has been released, after nine people were shot dead by security forces ahead of Wednesday’s elections, according to his party. Zanzibar, an Indian Ocean archipelago, is a semi-autonomous state of the East African country of Tanzania and both are due to elect their presidents and lawmakers in Wednesday’s election. Tanzanian President John Pombe Magufuli, whose government is accused of muzzling political dissent and independent media - accusations officials deny - is widely expected to win over his rival, Tundu Lissu, and secure another five-year term. In a statement early on Tuesday, the ACT-Wazalendo party said its veteran candidate for Zanzibar’s presidency, Seif Sharif Hamad, was detained at a polling station after going to cast his ballot in advanced voting. The party tweeted later in the day that their leader had been released. It also said nine people had been shot dead by security forces since Monday. Eight died on the island of Pemba, it said, after clashes between security forces and people who had been trying to stop the army distributing ballot boxes on Monday which they suspected contained pre-ticked votes. ACT-Wazalendo said police fired tear gas at the demonstrators and then “resorted to live ammunition”. Police said they had no information about any deaths.