The protesters were closing in.

A convoy of about a dozen vehicles carrying Prime Minister Sheikh Hasina of Bangladesh out of her sprawling official residence tried at first to escape through the usual gate, then spun around and took a different route — and still found itself facing a crowd of demonstrators.

Thousands had defied a curfew, pushed through police barricades and poured into the heart of the capital, Dhaka, enraged by the killing of nearly 100 protesters the day before.

Ms. Hasina’s security detail appealed for reinforcements. Armored vehicles rushed to clear a path, and her car sped to a helipad. A helicopter whisked her to an airfield, where she boarded the military plane that would take her out of the country.

In her chaotic final hours on Monday as Bangladesh’s leader — recounted in conversations with nearly a dozen diplomatic, security and government officials, some of whom were caught in its panic — Ms. Hasina clung to the idea that she could hold out against the throng converging on her. According to three people with knowledge of the discussions, she resisted the advice of her security chiefs, who told her that their crackdown on antigovernment protests had failed after claiming some 300 lives over a few weeks, that trying to suppress them would require much more bloodshed.

Her decision to let go after 15 years in office, and to make what appears to have been a hastily arranged escape to India, did not ultimately come because of international pressure or a diplomatic push. Instead, according to security officials and diplomats who spoke on condition of anonymity to discuss the delicate matter, her top security advisers appealed to her closest family members to persuade her that it was the end.