"He fought for our independence, built a nation where there was none, and made us proud to be Singaporeans. We won't see another like him," Lee's son, Prime Minister Lee Hsien Loong said in an emotional televised address.

More than 11,000 people gathered at the main gate of the Istana state complex chanting "Mr Lee, Mr Lee", leaving flowers and cards, as a private family wake began inside the former British colonial headquarters.

His coffin will be carried on Wednesday atop a gun carriage to Parliament House, where it will lie in state for the public to pay respects, until his state funeral and cremation on Sunday.

World leaders paid tribute to Lee, describing the former prime minister as a powerful figure who had earned his place in modern history as a revered leader. Singapore's transformation from a British colonial backwater to one of the world's leading financial hubs is widely attributed to his leadership.

Lee was a "true giant of history," US President Barack Obama said in a statement following news of his passing.

"His views and insights on Asian dynamics and economic management were respected by many around the world," Obama went on to say. "No small number of this and past generations of world leaders have sought his advice on governance and development."

Chinese President Xi Jinping praised Lee as an "old friend of the Chinese people" and said he was "widely respected by the international community as a strategist and a statesman".

Lee Kuan Yew passed away early Monday morning at the age of 91. He had been hospitalized on February 5 with severe pneumonia.

Singapore's "founding father" began his political career in 1954 when he co-founded the People's Action Party (PAP). Five years later he became the city-state's first prime minister, an office he held until 1990.

"My greatest satisfaction in life comes from the fact that I have spent years gathering support, mustering the will to make this place meritocratic, corruption-free and equal for all races and that it will endure beyond me, as it has," Lee said in his book "One Man's View of the World" published in 2013.

During his tenure, Lee was credited with a strict rule that laid the groundwork for a stable nation with a booming financial sector and a low crime rate. Singapore is one of the world's richest countries on a per capita GDP basis.

Nevertheless, not all condolences praised the Asian leader. Human Rights Watch pointed to Lee's human rights record in light of his silencing of political dissent and implementation of harsh punishment for minor infractions.

Lee's "tremendous role in Singapore's economic development came at a significant cost for human rights," HRW Deputy Asia Director Phil Robertson told DW.

Furthermore, the government strictly controls freedom of speech and assembly. Singapore has become more liberal in last few years, but it still uses corporal and capital punishment and ranks 150th in the annual press freedom of Reporters Without Borders, below countries like Russia and Zimbabwe.

jil/jr (AP, AFP)