Malaysia's opposition Democratic Action Party has ousted the ruling National Front coalition in the northern state of Penang during Saturday's general election.
Officials and local media say the opposition Democratic Action Party is leading in races for at least 17 of the state legislature's 40 seats.
Other opposition parties are also poised to win at least six other seats in Penang.
In other results, the opposition Pan-Malaysian Islamic Party (PAS) will retain control of the northeastern state of Kelantan, previously the only state in Malaysia held by the opposition.
Polling began earlier Saturday amid allegations of fraud and violence.
In the northeast, police detained about 20 stone throwing opposition supporters, who were stopping buses transporting people to the polls.
Some opposition parties have accused the ruling coalition of busing unregistered voters to polling stations to rig the elections.
During the campaign, opposition leaders tried to chip away at the coalition's power by courting Malaysia's minority ethnic Chinese and Indians, who are currently members of the country's multi-ethnic ruling coalition.
Malaysia's ethnic minorities have complained about increasing discrimination by the country's majority Muslims in programs that favor Muslims in government jobs, business and education.
Prime Minister Abdullah is seeking a second term in office.
Some information for this report was provided by AFP, AP and Reuters.