Updated

Fang Lizhi, an astrophysicist whose speeches and writing on political liberalization were a key inspiration for China's pro-democracy movement in the 1980s, has died in the US at the age of 76.

Fang -- who in the 1980s famously compared Marxism to a worn-out dress, took refuge in the US embassy in Beijing in the wake of China's June 4, 1989, crackdown on pro-democracy protesters in Tiananmen Square, contributing to a rift between the countries.

He left China in 1990 with the help of the US, which flew him and his wife, Li Shuxian, to the UK on an American military plane.

A University of Arizona spokeswoman confirmed that Fang died Friday morning, though she said additional details were not available.

Before fleeing the country of his birth, Fang had led a tumultuous life, his distinguished career as a scientist often disrupted on account of his impassioned arguments for greater freedom of speech and thought.

Born in Beijing on Feb. 12, 1936, Fang studied nuclear physics at the prestigious Peking University, graduating in 1956. He was soon put to work helping with China's effort to develop nuclear power but was dismissed from the project and reassigned to the University of Science and Technology of China, or USTC, after criticizing restrictions faced by the country's intellectuals.

Like many of those then called "rightist" academics, he was sent down to the countryside during the Cultural Revolution and made to work in a coal mine.

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