Bangladesh's new chief justice has been sworn into office after his predecessor, viewed as a loyalist of toppled premier Sheikh Hasina, quit following protester demands, a presidential official said Sunday.

It is the latest in a string of fresh appointments to replace an old guard viewed as linked to the previous regime, ousted by the student-led uprising.

Syed Refaat Ahmed, the senior-most high court judge, was sworn into office by President Mohammed Shahabuddin, the president's press secretary Shiplu Zaman told AFP.

"He became the 25th chief justice of Bangladesh," Zaman said.

Ahmed studied at the University of Dhaka, Oxford and Tufts University in the United States.

Hasina, 76, fled by helicopter to neighbouring India on Monday as protesters flooded Dhaka's streets in a dramatic end to her iron-fisted rule.

Her government was accused of widespread human rights abuses including the extrajudicial killing of thousands of her political opponents over her 15-year rule.

Cabinet ministers left blindsided by her sudden fall have gone to ground, while several top appointees have been forced out of office -- including the national police chief and the central bank governor.

Ahmed's predecessor Obaidul Hassan on Saturday became the latest to announce his departure, after hundreds of protesters gathered outside the court to demand he step down.

Appointed last year, Hassan earlier oversaw a much-criticised war crimes tribunal that ordered the execution of Hasina's opponents, and his brother was her longtime secretary.

Bangladesh's interim leader, Nobel laureate, Muhammad Yunus, 84, returned from Europe this week to lead a temporary administration facing the monumental challenge of ending disorder and enacting democratic reforms.