Bangladesh Prime Minister Sheikh Hasina has stepped down from office, ending 15 years of what the opposition says was “authoritarian rule” and sparking celebrations across the country.

General Waker-uz-Zaman, the chief of army staff, said in a statement on Monday that an interim government will take over with immediate effect and asked citizens to keep their trust in the army.

“I request you all to be a little patient, give us some time and together we will be able to solve all the problems,” Zaman said. “Please don’t go back to the path of violence, and please return to nonviolent and peaceful ways.”

Hasina resigned after weeks of protests against quotas for government jobs flared into nationwide unrest. At least 280 people were killed and thousands injured as the government cracked down on the demonstrations.

Hasina reportedly fled the country on Monday in a military helicopter to India, a strong ally of the former leader. Video reports by local news media, showed thousands of people storming the prime minister’s residence, chanting and singing in celebration as they ransacked it.

Here’s the background that led up to the historic moment:

What happened on Sunday?

More than 90 people were killed on Sunday alone as clashes between security officials and demonstrators escalated and protesters called for Hasina to step down.

Police fired rubber bullets and tear gas on a huge crowd of protesters in Shahbagh Square in the capital, Dhaka. Demonstrators in the northwestern district of Sirajganj also attacked a police station, killing at least 13 officers.

Sunday saw the highest recorded single-day death toll since the protests broke out last month.

Authorities imposed a “shoot-on-sight” curfew from 6pm (12:00 GMT) on Sunday and flooded the streets with police and military units to restore order.

But thousands of people marched largely unrestrained early on Monday, defying the curfew, although there were reports of clashes outside the capital.

However, as protesters started to hand flowers to the military about noon and as officers in turn embraced the demonstrators, it was clear that something had changed very quickly, Al Jazeera’s Tanvir Chowdhury said, reporting from Dhaka.

“People are relieved that this brutal crackdown is finally over. It is game over for Hasina.”

What initially caused the protests?

The demonstrations began in July in Dhaka and were initially led by students angry at a court’s reinstatement of a job quota scheme that was rescinded in 2018.

The policy reserved 30 percent of government jobs for descendants of veterans who fought in the 1971 war of independence from Pakistan – most of whom are linked to Hasina’s Awami League party, which led the independence movement.

A further 26 percent of jobs were allocated to women, disabled people and ethnic minorities, leaving open about 3,000 positions for which 400,000 graduates compete in the civil services exam. A fifth of Bangladesh’s 170 million people are unemployed.

Rallies against the quotas intensified after Hasina referred to the protesters as “Razakars”, which refers to people who collaborated with Pakistan during the 1971 war.

From July 10 to July 20, more than 180 people were killed in some of the worst periods of unrest during Hasina’s 15-year tenure. Police said protesters vandalised property and torched government buildings, including a national television station.

The Supreme Court rescinded the job quota policy on July 21, ruling that 93 percent of jobs would instead be open to candidates on merit.

But the protests continued unabated as students and other citizens assembled in a new wave of rallies. They called for justice for those killed and pressed a new, singular demand – that Hasina step down.

Hasina and members of her cabinet sounded defiant until the end, accusing opposition forces of fuelling the protests. On Sunday, Hasina called the protesters “terrorists”.

Why was Hasina unpopular?

The world’s longest serving female head of government, Hasina, 76, is the daughter of Bangladesh’s founding father, Sheikh Mujibur Rahman. She was first elected as prime minister in 1996 and again in 2009, serving a total of 20 years in office.

Although Hasina won her fourth straight term in elections this year, she was accused of muzzling opposition forces and other forms of dissent, orchestrating disappearances and arranging extrajudicial killings. Hasina rejected the allegations.

But as student protesters grew increasingly bold in July and chanted, “One, two, three, four, Sheikh Hasina is a dictator,” analysts speculated that Hasina would not be able to survive the biggest challenge to her rule.

“A dictator has fallen,” political analyst Mubashar Hassan, who said he has lived in exile in Australia for years, told Al Jazeera on Monday as news of Hasina’s ouster broke and television visuals showed protesters in Dhaka climbing atop a large statue of Hasina’s father, chiselling away at the head with an axe.

“This is an incredible moment. This is like a second independence of Bangladesh,” he said. “[Bangladesh has been] shackled by the tyranny of Sheikh Hasina and her regime. I couldn’t go back to Bangladesh since 2018, and hopefully, I’ll see my family soon.”

Was deploying the army the tipping point?

Hassan said the government’s decision to deploy the army against the protesters appeared to be the tipping point that collapsed Hasina’s rule.

The army is largely perceived in Bangladesh as a neutral entity and is well-trusted and respected by most people. In 2008 when an electoral crisis threw the country into a political stalemate, the military stepped in and ensured that elections were held in December that year.

As the latest protests escalated, the army was cautious in its statements and appeared to be neutral.

But on Friday, former military personnel expressed support for the protests, criticising the decision to remove border patrol units to quell the demonstrations. Former army chief Iqbal Karim Bhuiyan even turned his Facebook profile picture red in a show of support, hinting at the general mood in the military.

Another tipping point, Professor Naomi Hossain of the United Kingdom’s School of African and Oriental Studies said, was the fear that there would be “an absolute bloodbath” on Monday as protesters again started to mobilise despite Sunday’s killings.

“There was a very genuine and well-founded fear that today was going to be bloody,” she said on Monday. “… People were very fearful that today would be a bloodbath, so this really pushed the military into thinking about what they needed to do.”

What will the new government look like and what’s next?

Details of how the interim government will be formed are still sketchy, but Zaman said he was holding talks with major political parties, including the opposition Bangladesh Nationalist Party.

It is not clear if the military itself will take power  as has been done in several military coups in the past. Student activists have said they would reject military rule.

“We cannot afford that. … We are really hoping that the army is able to keep the peace as well as introduce some kind of interim system that can deliver us back to democracy,” Hossain said.

Zaman also said the deaths in the course of the weeks-long protests would be investigated as calls for justice grew.

“I promise you all, we will bring justice to all the murders and injustice. We request you to have faith in the army of the country. I take full responsibility, and I assure you to not get disheartened,” the general said.

Meanwhile, Hasina arrived with her sister in Agartala, the capital of India’s northeastern state of Tripura, according to reports in Indian media.