India, Dec. 21 -- Bangladesh's chief adviser leader Muhammad Yunus on Saturday vowed to carry forward the ideals of slain youth leader Osman Hadi, telling tens of thousands of mourners at his funeral that the country was making a collective promise to honour what the young politician stood for, even as tight security blanketed the capital amid ongoing unrest.

Hadi, 32, a prominent figure in last year's student-led uprising that toppled longtime prime minister Sheikh Hasina, was shot in the head by masked assailants in Dhaka last week while launching his campaign for elections due in February. He died on Thursday in Singapore after spending six days on life support.

His killing has triggered a fresh wave of instability in the South Asian...