Who is Nahid Islam, student leader of campaign to oust PM Sheikh Hasina?

Often seen in public with a Bangladeshi flag tied across his forehead, Nahid Islam is a soft-spoken sociology student who spearheaded the protest that ousted Prime Minister Sheikh Hasina after 15 straight years in power.

Islam, 26, was the coordinator of a student movement against quotas in government jobs that morphed into an oust-Hasina campaign. He rose to national fame in mid-July after police detained him and some other Dhaka University students as the protests turned deadly.

Nearly 300 people, many of them college and university students, were killed in weeks of violence across the country that only abated when Hasina resigned and fled to neighbouring India on Monday.

Read more: Bangladesh students set deadline for parliament dissolution after PM Hasina's exit

Islam, who speaks unemotionally but firmly in public, has said the students would not accept any government led or supported by the army and has proposed that Nobel laureate Muhammad Yunus be the chief adviser.

"Any government other than the one we recommended would not be accepted," he said in a Facebook post early on Tuesday.

On Monday, flanked by other student leaders, the bearded and stocky Islam told reporters: "We won't betray the blood shed by the martyrs for our cause.

"We will create a new democratic Bangladesh through our promise of security of life, social justice and a new political landscape."

He vowed to ensure the country of 170 million never returns to what he called "Fascist rule" and asked fellow students to protect its Hindu minority and their places of worship.

Islam, who was born in Dhaka in 1998, is married and has a younger brother, Nakib. His father is a teacher and his mother a homemaker.

"He has incredible stamina and always said the country needed to change," Nakib Islam, a geography student, told Reuters. "He was picked up by the police, tortured until he was unconscious, and then dumped on the road. Despite all this, he continues to fight. We have confidence that he will not give up. Proud of him."

Sabrina Karim, associate professor of government at Cornell University who specialises in studying political violence, called Monday a historic day for Bangladesh.

"This might very well be the first successful Gen Z-led revolution," she said. "There is perhaps some optimism for a democratic transition even if the military is involved in the process."