By Ruma Paul
DHAKA (Reuters) - Bangladesh's main opposition party on Tuesday boycotted three mayoral elections over accusations of massive rigging, fanning fears of further unrest in the South Asian nation.
Political uncertainty has prevailed since January 2014, when Prime Minister Sheikh Hasina's Awami League won a second consecutive term after a bloody parliamentary election boycotted by the main opposition Bangladesh Nationalist Party (BNP).
The BNP, led by rival Khaleda Zia, has stepped up protests this year to try and force Hasina to step down and hold a new vote after last year's poll, deemed by international observers to be flawed.
Tuesday's mayoral elections were for two city corporation posts in Dhaka, the capital, and one in the port city of Chittagong, with a total of 6 million voters eligible.
The elections were supposed to be nonpartisan, but both the ruling party and the BNP directly backed candidates.
"This is not an election," senior BNP leader Moudud Ahmed told reporters. "The ruling party are voting for themselves by capturing polling centers."
Voter turnout was barely 5 percent, he said, adding, "We participated in the city polls to restore democracy. But vote rigging has already proved that restoring democracy is not possible under this government."
The BNP pulled out of polls because it anticipated defeat, said ruling party leader Mahbubul Alam Hanif.
"It was pre-planned," he said. "They boycotted the polls to create an issue for a fresh movement."
The United States urged impartial investigation of election irregularities, underlining the need to avoid violence.
"We are disappointed by widespread, first-hand, and credible reports of vote-rigging, intimidation and violence that have occurred at polling stations," the U.S. embassy in Dhaka said in a statement after polls ended, and vote counting began.
"It is important that irregularities be investigated transparently and impartially, and we call on all parties involved to work within the law and avoid violence at all costs."
Khaleda and leaders of her party had vowed retaliation if the local elections were rigged.
More than 120 people have been killed and hundreds injured in political violence, most in petrol bomb attacks on vehicles, amid transport blockades and strikes by the opposition aimed at toppling the government.
Political unrest over the past three months has cost at least 0.6 percent of the country’s gross domestic product.
Bangladeshi politics has been mired for years in rivalry between Hasina and Khaleda. Both are related to former national leaders and have alternated as prime minister for most of the past two decades.
(Reporting by Ruma Paul; Editing by Clarence Fernandez)