Fresh protests roiled Bangladesh on Saturday, just weeks after a deadly government crackdown, as demonstrators returned to the streets in what appeared to be the biggest numbers yet and escalated their demands to include the prime minister’s resignation.

In its efforts to break last month’s student-led protests, which started peacefully but turned violent after demonstrators were attacked, the government detained student organizers, rounded up about 10,000 people and accused tens of thousands more of crimes such as arson and vandalism.

A curfew and communications blackout quieted things down, and the students won a significant concession from the courts on their initial demand to end a preferential quota system for public-sector jobs.

But the crackdown by the security forces of Prime Minister Sheikh Hasina — which led to the deaths of more than 200 people — seems to have made many Bangladeshis even angrier and broadened the movement’s scope.

As they gathered in huge numbers on Saturday, the demonstrators whittled their demands to a single — and highly provocative — request. Previously, they had called for an apology by Ms. Hasina and the firing of some officials. Now, they are demanding the resignation of both her and her government as accountability for the hundreds of protester deaths.

The demonstrators called for further protests and a “complete noncooperation movement” until Ms. Hasina steps down.

“It is time for her to go,” Nahid Islam, one of the student leaders who was tortured in custody in recent weeks, said at Shaheed Minar, a national monument in Dhaka where teeming crowds gathered on Saturday. “It is not enough to just oust Sheikh Hasina; the murders, looting and corruption that have taken place in this country must see justice.”

In an indication of the risk of violence in the days ahead, Ms. Hasina’s ruling Awami League called for gatherings of its own across the country on Sunday and Monday.

The protests began largely peacefully in early July, after a Dhaka court reinstated quotas for more than half of all civil service jobs, which are highly sought after. Under pressure from protests in 2018, Ms. Hasina had paused the decades-old system that gave preference to, among others, descendants of people who fought for Bangladesh’s independence from Pakistan.

Students called the quotas discriminatory. But anger over the issue was also expressive of broader unhappiness with an economy that has stagnated in recent years, and an increasingly authoritarian governing party in which cronyism was entrenched, analysts said.

Ms. Hasina’s initial response to the protests was dismissive, fueling a perception that she favored reinstating the quotas as an offering to her supporters after winning a fourth consecutive term in January.

On Saturday, Ms. Hasina again spoke of conciliation, a tone that for many clashed with the violence of the earlier crackdown. “The door of Ganabhaban is open,” Ms. Hasina said, referring to her official residence. “I want to sit with the agitating students of the movement and listen to them. I want no conflict.”

Ms. Hasina’s government blamed last month’s violence on her sworn political enemies, the Bangladesh Nationalist Party and the Bangladesh Jamaat-e-Islami, an Islamic party, and rounded up their leaders. She also issued a decree banning the political activities of Jamaat-e-Islami and its student wing. Ms. Hasina’s lieutenants put some arrested student leaders on camera, where they read a statement declaring the end of their movement.

But the moment the government eased up on the restrictions, the protesters began demanding justice for their peers who had been killed, wounded or detained. Once the student leaders were freed, they said they had been forced to make that statement, and they repeated their call for mass gatherings.

Mr. Islam, the student leader who called for Ms. Hasina’s resignation on Saturday, was picked up by the security forces shortly after the crackdown began around July 16. When he was released days later, his sister Fatema Tasnim said he had been tortured. He had bruises on his arms, and his thighs had turned black from beatings. He was picked up again days later while receiving treatment at the hospital.

The political culture in Bangladesh has long been violent. But many saw the targeting of students and other young people by Ms. Hasina’s government as crossing a line.

The Bangladeshi newspaper Prothom Alo examined 175 of the more 200 deaths. The paper found that 137 of the bodies had bullet wounds, and that more than 100 of the dead were people under 30. UNICEF said that at least 32 children were killed in the crackdown.

The protesters had returned to the streets after congregational noon prayers on Friday, the start of the weekend in Bangladesh, with thousands braving rain across the country to participate. Late in the afternoon, clashes between the protesters and security forces were reported across the country. At least two people were killed, including one police officer.

“There’s a storm inside my chest,” a group of protesters gathered near Dhaka College chanted on Saturday. “I’ve bared my chest, go ahead and shoot.”

Salimullah Khan, a university professor who joined the protests once they resumed, said there was anger over the killings, and no trust that the same authorities who administered the crackdown would deliver justice.

“How can you ask a killer to bring justice to a murder?” he said. “These killings were state sponsored, carried out by state forces and their collaborators.”

Anupreeta Das contributed reporting from New Delhi.