Kenyan opposition leader Raila Odinga has died in India, Indian police said Wednesday. He was aged 80. President William Ruto declared a seven-day mourning period, calling Odinga's death an "immense and immeasurable loss." Odinga will be honored with a state funeral, and Kenyan flags will fly at half mast during the mourning period. Odinga died of a heart attack, according to AP news agency, which cited the Devamatha Hospital in India's Kerala State. French news agency AFP reported that Odinga died during a "health visit" to the South Asian nation. Indian police told AFP he was walking with his sister, daughter and a personal doctor "when he suddenly collapsed." Often described as Kenya's most influential opposition figure, Odinga spent more than three decades at the heart of the nation's political transitions, championing multi-party democracy, challenging entrenched power and negotiating peace in moments of deep national crisis. Raila Odinga waves to the crowd from a podium deocrated with a giant 'R' for RailaRaila Odinga waves to the crowd from a podium deocrated with a giant 'R' for Raila Kenyan President William Ruto has called Odinga's death an 'immense and immeasurable loss'Image: Raila Odinga press Team Who was Raila Odinga? Born January 7, 1945, in Maseno, Kisumu County, in western Kenya, Raila was the son of Jaramogi Oginga Odinga, a leading figure in Kenya's struggle for independence who later became the country's first vice president. Raila's early schooling was at Kisumu Union Primary, then Maranda High School. In 1965, he won a scholarship to study in the German Democratic Republic (GDR), East Germany, during the Cold War. By 1970, he had graduated with an engineering diploma (roughly equivalent to a master's) in mechanical engineering. After returning home, Raila worked briefly as a lecturer at the University of Nairobi and later at the Kenya Bureau of Standards. He also launched a manufacturing venture, Standard Processing Equipment Construction & Erection (later East African Spectre), dealing in LPG cylinders and related apparatus. Early political career and the advent of multi-partyism Raila's political life was deeply shaped by the fraught politics of Kenya's KANU one-party era in the 1980s. He was often arrested and detained without trial for his multi-party activism. Over time, he gravitated into organized opposition. In 1992, he was elected as a member of parliament (Langata constituency), marking his formal entry into national politics. In 1997, Odinga made his first presidential bid, finishing third behind President Daniel arap Moi and Mwai Kibaki.