KUALA LUMPUR, Malaysia (AP) -- At least 50,000 Malaysian opposition supporters rallied at a stadium Wednesday to protest what they say are fraud-marred election results that enabled the long-ruling coalition to cling to power.
Opposition leader Anwar Ibrahim's three-party alliance believes the National Front coalition used illegal voters, bogus ballots and other irregularities in May 5 national polls to extend its 56 years of rule. Prime Minister Najib Razak has rejected the accusations and maintained that the elections were free and fair.
The National Front won 133 of Parliament's 222 seats, but Anwar's alliance plans to mount a legal challenge of the results of at least 30 seats. The National Front lost the popular vote, polling 5.24 million votes to the opposition's 5.62 million.
Opposition supporters filled a sports stadium Wednesday night for a rally marking the start of a campaign to demand more electoral transparency. Standing with umbrellas under a drizzling rain, they wore black clothing including T-shirts with slogans such as "Democracy is dead" and "Stay strong Malaysians."
Anwar said he was grateful to the crowd for "showing the courage and conviction to change the course of history" in Malaysia.
"This is the beginning of a battle between the people and an illegitimate, corrupt and arrogant government," Anwar told the cheering audience.
The National Front, which has governed since independence from Britain in 1957, survived its most competitive elections ever as public frustration soared over claims of government graft and racial insensitivity. It held 135 seats in Parliament before the legislature was dissolved last month and failed on Sunday to regain the two-thirds parliamentary majority it had enjoyed for decades.
Prime Minister Najib's office criticized Anwar in a statement Wednesday, saying his accusations of fraud were unfounded and his rally was irresponsible.
"No doubt his latest claims will also evaporate on close inspection," the statement said. "His protest is calculated to create unrest."
In Washington, the White House on Wednesday congratulated Najib on his coalition's victory, but said it was important that Malaysian authorities address concerns over reported election irregularities.
"We look forward to the outcome of their investigations," the U.S. statement said.
The Institute for Democracy and Economic Affairs, a Malaysian think tank that was accredited by electoral authorities to observe the elections, said Wednesday the vote was "only partially free and not fair."
Public doubts remain about the integrity of the voters' registration roll and the Election Commission's impartiality, the institute said in a report.
The Prime Minister's Office said it rejected some of the institute's claims, especially "those which refer to 'perception' rather than fact."
Many opposition supporters believe the National Front relied on gerrymandering of constituencies and also stuffed ballot boxes in closely fought constituencies and used foreign migrants from countries such as Bangladesh to vote illegally.
The National Front lost ground mainly among urban, middle-class voters. Its electoral support remained strong in rural districts where government handouts have helped poorer citizens whom the opposition failed to convince with its pledges of creating a cleaner government.
Associated Press writer Matthew Pennington in Washington contributed to this report.
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