A Bangladeshi court has issued an arrest warrant for former prime minister and current opposition leader, Khaleda Zia, over a deadly fire-bomb attack on a bus in the capital, Dhaka, last year.

On Wednesday, the Dhaka court accused Zia and 27 other officials and activists of her Bangladesh Nationalist Party (BNP) of instigating the assault as part of an anti-government campaign of arson.

Prosecutor Shah Alam Talukdar said Zia was “the main accused in the case.”

However, BNP spokesman, Ruhul Kabir Rizvi, dismissed the charge brought against the ex-premier as "laughable,” saying, "This is politically motivated and is part of deep conspiracy against her.”

It was not immediately clear whether the police would act on Wednesday’s court order as another arrest warrant issued against Zia last year was never executed.

The judge urged the police to report to the court on April 27 about the execution of the warrant.

Meanwhile, police said up to 200 BNP supporters held a demonstration outside the party headquarters in Dhaka after the news of the court order emerged.

Assistant commissioner of Dhaka Metropolitan Police Saifur Rahman said the protesters shouted slogans during the “impromptu” event, but “they moved back to the party office before police reached the spot.”

Over the past few years, Bangladeshi politics has been mired in rivalry between Zia and Prime Minister Sheikh Hasina, the head of the ruling Awami League party.

Hasina has blamed Zia for using violent tactics in opposing the government, but the ex-premier has dismissed the allegation.

In January 2014, Hasina became the prime minister for the third time after winning the 2014 general election, which was boycotted by the BNP and its allies.

Supporters of Bangladesh Nationalist Party (BNP) gather for a protest rally as they mark the second anniversary of a general election boycotted by the party and its allies in Dhaka, Bangladesh, January 5, 2016. ©AP

The bus attack cited in Zia's case took place in January 2015 during a nationwide blockade of roads, rail and waterways, which was called by Zia in a bid to force Hasina to step down and prepare the ground for new elections in the South Asian country.

The blockade unleashed three months of protests that paralyzed the country and left more than 120 people dead.

Demonstrators fire-bombed buses and trucks while police responded by firing live rounds.

Some 15,000 opposition supporters and dozens of BNP senior officials were detained as part of the government crackdown launched in the wake of the unrest.