In Zanzibar, the ruling and opposition parties have accused each other of instigating election-related violence that left at least 15 people injured.
A spokesman for the ruling Chama Cha Mapinduzi (CCM) says opposition supporters provoked the violence by throwing stones at a crowd of ruling party supporters.
But a Civic United Front (CUF) official says followers of the ruling party sparked the unrest, hurting 10 opposition supporters.
Authorities say the violence on Tanzania's semi-autonomous island erupted late Sunday after separate campaign rallies by the ruling and opposition parties.
Island residents go the polls October 30 for Tanzania's general elections. The opposition CUF lost to the ruling party in 1995 and 2000 in Zanzibar and complained of fraud during both elections.
Some information for this report provided by AFP and Reuters.