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Yen Lee was 39 when a bullet ended his life on March 6, 1947. He was among 50 Taiwanese journalists executed that day for criticizing the Nationalist government of China, which had taken back Taiwan from Japan at the end of World War II.

Their deaths, granddaughter Hsinning (Beca) Lee told NBC News, were part of the first wave of a government purge that claimed the lives of thousands.

On Tuesday, Taiwanese both on the self-ruled island of 23 million and abroad will mark the 70th anniversary of this crackdown, which began on Feb. 28, 1947, and is remembered as the 228 Incident.

“This is something I want to pass on to my children — to speak up, fight for what's right for ourselves and people different from us. Democracy is something that should not be taken for granted.”

“I think it’s quite timely with the political climate now, how fragile freedom of speech can be, and how divisive we can become against each other very quickly,” said Lee, a graphic designer who immigrated to the United States from Taiwan when she was 15.

For decades, the 228 Incident was a taboo topic that many victims’ families did not discuss. The fear of political persecution always loomed large, Lee said, a feeling also shared to some extent by her family.

Less than two years before Lee’s grandfather was killed, Japan had surrendered to end World War II and returned Taiwan, a former colony for a half-century, to China’s ruling Nationalist party.

The Taiwanese initially welcomed the Nationalists, but tensions soon flared. The flashpoint came on Feb. 27, 1947, when officials questioned a Taiwanese woman selling black-market cigarettes. An agent struck the woman in the head with the butt of his gun, angering onlookers, according to a description of the events by the U.S. Department of State. Amid the chaos, a fleeing official fired into the crowd, killing a bystander.

Relatives of victims of "White Terror" hold lilies as they walk past a pond full of lilies during a memorial to mark the 22nd anniversary of the end of martial law, in Taipei, July 15, 2009. The "White Terror" period began soon after the 228 Incident in 1947, during which a military crackdown took place against dissidents protesting against the administration of Chen Yi, a governor appointed by Chiang-Kai-shek to help rebuild Taiwan after World War II. Pichi Chuang / Reuters

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The next day, protests erupted outside government offices, and military police opened fire on demonstrators, injuring and mortally wounding dozens. Unrest continued until troops from China arrived on March 8.

A bloody massacre and crackdown ensued, leaving between 18,000 and 28,000 dead, according to a 1992 report from the Executive Yuan — the executive branch of Taiwan’s government — cited by The China Post and other media. The exact number still remains a source of debate.

Lee said her grandfather’s death took an emotional and financial toll on the family.

Yen Lee, a journalist in Taiwan, was 39 when he was shot to death on March 6, 1947. Courtesy of Hsinning (Beca) Lee

“Obviously at that time, my grandfather was the main source of income,” she said. “It was very difficult for my grandma to raise six children on her own.”

But she did. Lee’s grandmother, who died 20 years ago, started a small business in the southern Taiwan fishing village where she lived. Lee said her grandmother would ride her bike more than 11 miles to the city to sell seafood and small goods.

Her father’s four older sisters also gave up their education to support the family, Lee said, a sacrifice that allowed her father, Yi-Hung Lee, and his younger brother to attend school.

Through it all, Lee’s family lived for decades under martial law, enacted by Nationalist party leader Chiang Kai-shek in 1949, the same year the Nationalists lost the Chinese civil war to the Communists and fled to Taiwan.

It also marked the beginning of the “White Terror” period, when those believed to be anti-government in Taiwan were rounded up and imprisoned, some executed. Martial law was eventually lifted in 1987, a first step toward Democratic rule.

Today, the 228 Incident is still wrought with political tension between the Nationalist party (KMT) and the Democratic Progressive Party (DPP), formed in 1986. The DPP, an opposition party, has tended to favor independence from China, which claims Taiwan — whose government calls it the Republic of China — as a breakaway province that must be reunited.

Pictures of victims of "white terror", in which about 140,000 people were either imprisoned or executed for their real or perceived opposition to the Kuomintang (KMT) government led by Chiang Kai-shek, are displayed during a protest against former Taiwan President Ma Ying-jeou in front of the Presidential Office in Taipei, Aug. 9, 2008. Pichi Chuang / Reuters

In 1995, former Taiwan President Lee Teng-hui apologized for the 228 Incident; a compensation fund was later set up for victims and their families. Lee said each family received around $195,000.

To mark the 70th anniversary, Taiwan President Tsai Ing-wen, of the DPP, will attend a ceremony Tuesday at the 228 Peace Memorial Park in Taipei with Taiwan Premier Lin Chuan and Taipei Mayor Ko Wen-je. It’s one of a number of events planned in Taiwan and abroad.

“I think it’s quite timely with the political climate now, how fragile freedom of speech can be, and how divisive we can become against each other very quickly.”

While Tsai’s approval ratings have dipped since her 2016 election as Taiwan struggles with a sluggish economy, her participation in this year’s commemorative events is welcoming for some.

“Having a government that Taiwanese people elected that appears to have the Taiwanese people’s interest [in mind] is, I think, very significant,” said Lee, whose parents and older sister still live in Taiwan.

As a mother of two living in upstate New York, Lee said her own father’s participation in political rallies and social movements supporting Taiwan independence has taught her the importance of civic engagement.

“This is something I want to pass on to my children — to speak up, fight for what's right for ourselves and people different from us,” Lee said. “Democracy is something that should not be taken for granted.”

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