Khaleda Zia, who was the country's first female head of government, had been suffering from a prolonged illness

Former Bangladesh Prime Minister Begum Khaleda Zia passed away at the age of 80 in a Dhaka hospital on Tuesday after battling prolonged health issues, her Bangladesh Nationalist Party (BNP) said in a statement.

She was the South Asian nation's first female prime minister, serving as the head of the government from 1991 to 1996 and 2001 to 2006.

"I am deeply saddened and grief-stricken by her death," Muhammad Yunus, chief adviser of the interim government of Bangladesh said. He added that Zia "represented an important chapter" in the history of Bangladesh.

"Despite political differences, her long political journey dedicated to national welfare, her people-oriented leadership, and her firm resolve always showed the way," Yunus said.

Zia's death was also mourned by Indian Prime Minister Narendra Modi and Pakistani Prime Minister Shehbaz Sharif.

Besides serving as leader of the opposition twice, Zia was the country's first lady from 1977 to 1981. Her husband Ziaur Rahman, Bangladesh's sixth president, was assassinated by members of the country's army in 1981. A bitter rival of former prime minister Sheikh Hasina, Zia faced several corruption cases but was acquitted by the country's Supreme Court.

Last week, her son Tarique Rahman, acting chairman of the BNP, returned to Dhaka after nearly 17 years in exile. Rahman is projected to be a key contender in the country's general elections, which are to be held in February.

On Monday, the National Citizen Party (NCP), which was born out of the protest movement that ousted Hasina last year, said it has formed an electoral alliance with Jamaat-e-Islami - an Islamist party. This has caused a rift in the NCP, which has positioned itself as a centrist, reformist alternative to the BNP and Hasina's Awami League.

In recent days, Bangladesh has seen a wave of violence prompted by the murder of Sharif Osman Hadi, one of the most prominent leaders of the 2024 uprising, who was shot by masked assailants in Dhaka earlier this month.

Following his death, protesters took to the streets throughout the country, demanding the arrest of the assailants, chanting anti-India slogans, and rioting. Protesters attacked and set fire to the offices of two prominent newspapers.