DHAKA, Bangladesh--Police in Bangladesh's capital fired tear gas to disperse supporters of the main opposition party who threw stones at security forces during a massive rally demanding the resignation of Prime Minister Sheikh Hasina and the transfer of power to a non-partisan caretaker government to oversee general elections next year.

At least one policeman died and dozens of others were injured, alongside scores of opposition supporters, police and witnesses said.

Dhaka police spokesman Faruk Hossain told The Associated Press that violence late Saturday raged in at least 10 spots in Dhaka, where security forces confronted opposition activists who attacked them, vandalized vehicles and torched vehicles.

An opposition spokesman, Zahiruddin Swapan, said more than 1 million activists joined their rally, but Hossain put the number at about 200,000.

The violence broke out at the Kakrail area in Dhaka when activists of the Bangladesh Nationalist Party led by former Prime Minister Khaleda Zia allegedly attacked a bus carrying the ruling Awami League's members to a separate rally a few blocks away, witnesses and media reports said.

Footage on Somoy TV station showed a roadside police box was on fire, torched vehicles and shattered glass from a building. Violence spread by Saturday afternoon as security officials fired sound grenades and tear gas at the rally venue where Zia's supporters chanted anti-government slogans.

Mirza Fakhrul Islam Alamgir, secretary general of Zia's party, announced a daylong general strike across the country on Sunday, accusing security forces of ruining a “peaceful” rally.

“Our rally was peaceful. But the authorities have used excessive force to ruin our rally. They attacked our people mercilessly,” Swapan said.

Ekattor TV station reported that a police hospital also was attacked. An Associated Press team at the scene said that violence had spread in the area and many people took cover in nearby alleys.

The ruling party had earlier warned that any attempt to trigger violence would be met with force.

Authorities deployed about 10,000 police while paramilitary border guards were also seen near the opposition's rally site.

In the southeastern district of Chattogram, Hasina criticized the opposition for holding the rally, saying that Zia’s party was attempting to derail her government’s development agenda.

“Today BNP (Zia's party) wants to oust the government. They are giving various types of threats to launch a movement ... No threat will work,” she told a huge rally at Anwara in Chattogram, where she inaugurated a Chinese-built underwater tunnel.

The opposition says it is attempting a final push to remove Hasina as the Election Commission prepares to announce the country’s 12th national election, expected to be held in January.

The rivalry between Hasina and Zia has been ongoing for decades, and Hasina’s government has been under pressure for months as the opposition has held largely peaceful anti-government demonstrations.

Alamgir, secretary-general of Zia's party, said it would continue to push for the resignation of Hasina's administration and the installation of a caretaker government.

“We don't trust this government. They must go first to hold a free and fair election. Otherwise they would rig the election,” he said in a recent interview with The Associated Press.

Hasina hopes to return to power for a fourth consecutive term and says the election should be held under her government’s supervision as specified in the constitution.

The U.S. State Department said in September it was taking steps to impose visa restrictions on individuals responsible for undermining the democratic election process in Bangladesh. They include members of law enforcement, the ruling party and the opposition.

The Biden administration has made the push for free and fair elections in Bangladesh “a prime focus of its democracy promotion policy abroad,” said Michael Kugelman, director of the South Asia Institute at the Wilson Center.

The imposition of visa restrictions followed previous measures including restrictions on the country’s elite anti-crime force. Rights groups and the U.S. say the force, which has been credited for effectively handling Islamist militancy in the country, is responsible for many enforced disappearances of government critics and opposition activists. The restrictions have resulted in a decrease in the number of deaths in so-called “cross-fire” incidents in recent months, media reports said.

Rights groups and the U.S. also criticized the government for enacting a controversial cybersecurity law, saying it is designed to silence critics and the opposition, an allegation authorities deny. Critics have also slammed the recent jailing and subsequent release on bail of two Bangladeshi rights activists.

Hasina recently told parliament that the U.S. wants to remove her from power at any cost. But the opposition and critics have welcomed the move by the U.S., which is the largest importer of Bangladesh's garment products.

Reactions to the U.S. move in Bangladesh have broken down along partisan lines, Kugelman said. Hasina's administration slammed it as “meddling” while many critics welcomed it, saying they hope it will push back against what they view as Hasina's growing authoritarianism.

Recent elections in Bangladesh, especially the last one in 2018, were widely believed by the West to be flawed. The Awami League party doesn’t have a good track record of overseeing free and fair elections since Hasina returned to power in 2008.

Kugelman said the government and opposition “are on a collision course” and that “there’s a good chance we could see an election with no opposition participation."