Bangladesh has been hit by a wave of violence before a court verdict due against the toppled longtime Prime Minister Sheikh Hasina, with her party calling for a nationwide “lockdown” to protest the case.

Schools in the capital Dhaka and other major cities went online on Thursday amid severe transport disruption, following a sharp rise in attacks.

As tensions mounted, the country’s authorities recorded 32 crude bomb explosions on Wednesday, with dozens of buses set on fire across the country.

No casualties were reported when two more crude bombs went off near Dhaka airport on Thursday night.

The interim government of Nobel Peace Prize laureate Muhammad Yunus has increased security measures, deploying 400 soldiers from the paramilitary Border Guard across the capital.

Meanwhile, checkpoints have been strengthened and public gatherings heavily restricted.

The recent violence has included a fire bomb being thrown at a government office in Gopalganj district, which is Hasina’s ancestral home. Local media also reported that an office of Grameen Bank, which Yunus founded, was torched in eastern Bangladesh on Wednesday.

Police have arrested dozens of supporters of Hasina’s Awami League party over their alleged involvement in explosions and sabotage.

Hasina, who fled to India last August during deadly antigovernment protests, is being tried in absentia for crimes against humanity. She denies any wrongdoing, claiming the trial is politically motivated.

The 78-year-old is accused of being the “mastermind and principal architect” behind Bangladeshi security forces’ violent suppression of demonstrations last year, which were prompted by a controversial government job-quota system.

As many as 1,400 people may have been killed in the violence, according to the United Nations.

The daughter of Bangladesh’s founding father, former President Sheikh Mujibur Rahman, Hasina first came to power in 1996, six years after she led a pro-democracy uprising that toppled the military ruler Hossain Muhammad Ershad.

After becoming prime minister again in 2009, Hasina ruled for 15 years until last August. Rights groups say her second premiership was autocratic, pointing to abuses such as arrests, disappearances and extrajudicial killings.

Yunus, the interim prime minister, said he inherited a “completely” broken political system from her.

The 85-year-old Nobel Peace Prize winner announced on Thursday that the nation of 170 million would hold a referendum on a national charter signed last month. It will take place on the same day as parliamentary elections in February, he said.

His interim government has promised to end state violence, but a new report by the Bangladeshi rights group Odhikar suggests impunity is still rife, which has allowed such abuses to flourish.