Twelve hundred Zambians gathered on a sunny morning in August of 2012 to protest at Collum Coal Mine, which is located in a rural southern province and, at the time, was owned by five Chinese brothers. They were angry about the working conditions in the mine: Collum had been cited several times by Zambia’s government for labor violations, and miners said that they felt unsafe working there. They were also upset about annual wage increases that they said amounted to only a single Zambian kwacha—the equivalent of twenty cents.

The miners learned that a Chinese foreman had brought outside workers to replace them during the protest, according to one of the protesting miners, twenty-eight-year-old Robert Mundike. Mundike and his co-workers confronted the foreman at one of the mine’s shafts and assaulted him. Then, according to Mundike, they beat up more Chinese workers, along with Zambian miners who were still working even though the protesters had told them not to.

The group—which included not only Collum miners but also their relatives and former workers who said they were owed wages—was becoming restless. They reached another mine shaft, near a cluster of houses where several Chinese supervisors lived. Five Chinese men ran from the settlement, past the coal-carrying conveyor belt and a rock crusher and into the mine, Danny Sikatari, who works as a mine foreman but who did not participate in the protest, told me. The mine entrance was at the bottom of a steep hill. Protesters went to the top, which was sooty from the raw coal, and unhooked a steel, one-ton trolley that stood on a path of railroad tracks. They then pushed it, hard, into the mouth of the mine. One Chinese man, Wu Shengzai, was hit and killed. Two others were hurt.

Several protesters did not know someone had died until hours later, after the police had been called and the mob had dispersed. “We did not want to kill him,” Mundike, who has a frail frame and eyes that nearly fill his face, said. “We just wanted to destroy everything in the tunnel and in the mine.”

Chinese companies operate two thousand enterprises in more than fifty African countries; of those, five hundred are in Zambia. The appeal is obvious: China is one of the world’s biggest users of copper, which is used to make everything from coins to frying pans, and Zambia has the second-largest reserves of raw copper in Africa, among other precious resources like coal, nickel, uranium, and gemstones.

In 2008, China and Zambia set up a zone in which Chinese investors didn’t have to pay taxes to the Zambian government—China’s first such zone in Africa—and fifty companies invested a total of eight hundred million dollars. As of the end of 2012, the Chinese government and private sector had together invested $2.5 billion in the nation. At least eighty thousand Chinese immigrants live in Zambia, which has a population of fourteen million. Partly as a result of all this investment, Zambia has a steadily growing economy. Its politics, though, have recently been dominated by officials who have been accused of enriching themselves by reaping the benefits of Chinese investment instead of using it to help the poor.

I have previously written about the tension between China and some African countries and have been specifically investigating Chinese coal-mining operations in Zambia. As the number of Chinese immigrants and businesses has risen during the past decade, the clash of cultures between the Zambians and the Chinese has intensified. A language barrier keeps many Chinese and Zambians from getting to know one another. In the mines, conflicts have proliferated between Zambian workers and their Chinese bosses. In 2005, at least fifty Zambians burned to death in an explosion at a factory at the Chinese-owned Chambishi copper mine.

Zambia’s President, Michael Sata, won election in 2011 partly by capitalizing on anti-Chinese sentiment. Chinese investors should be called “infestors,” he said during his campaign. Since his election, his administration has launched several investigations of corruption against leaders like Rupiah Banda, the former President, over graft charges. The administration is probing millions of dollars’ worth of kickbacks taken by former officials; Banda currently has several trials pending.

The Zambian government also passed new legislation in the spring that required foreign investors to put their revenue from exports in local bank accounts in order to help eliminate tax and royalty avoidance. (The 2013 Africa Progress Report, published by the Kofi Annan-led Africa Progress Panel, shows that Zambia collected only two hundred and forty million dollars in tax revenue from the copper mines’ ten billion dollars’ worth of exports in 2011.) Sata has also vowed to improve foreign investors’ compliance with Zambian labor laws.

Critics say he hasn’t gone far enough: Collum’s labor and safety violations continued after his election. Zambia’s labor and social security minister, Fackson Shamenda, waved off the incongruence, telling me the new leadership had spurred the miners into action to protest their conditions. “The workers realized there was a friendly government in place,” he said. In February, the government seized the Collum mine, citing repeated labor and safety violations and nonpayment of taxes and royalties. Now the Zambian government owns and operates the mine.

The five Xu brothers, who are from China’s Jiangxi Province, took over the coal deposits in the tiny village of Sinazeze from the Zambian government in 2000 and then built Collum Coal Mine. Zambia’s government was grateful for the venture. Sinazeze had until then been dominated by agriculture. The roads are rocky and uneven, and bordered by jagged rocks, drooping foliage, and wheat-colored weeds that sprout from the hilly terrain. The mine became the only one in the country extracting and processing coal, and the young men of Sinazeze jumped at the chance to make more money than they had been earning as farmers.

But early on, the mine’s owners clashed with the government. The Zambia Environmental Management Agency issued several citations to Collum in the past decade for severe air pollution and for contaminating water sources that served nearby communities. Collum paid the fines but refused to invest in more environmentally friendly equipment, the Agency said.

The labor difficulties began early, too. Chishimba Nkole, president of the Mine Workers Union of Zambia, told me that workers alleged that mine bosses beat them. The Chinese supervisors, detained by the police, would pay a bribe and be released, Nkole said. Collum managers avoided meeting with union leaders, he added, and when they did meet for salary negotiations, the meetings were highly charged.

On a mild day in October, 2010, hundreds of miners gathered outside a mine shaft to protest for higher pay. Across the shaft’s gate stood the miners’ Chinese supervisors, nervously clustered and holding guns. Workers had demonstrated in the past, and when they began demanding a promised pay increase their supervisors started shooting; at least eleven miners were wounded. Collum paid the injured miners modest settlements of between five thousand and eleven thousand dollars. The government eventually dropped charges against the supervisors and let them return to China.

“It has been a very tough experience,” Mundike told me. He described having his pay docked when he used the company ambulance to rush his child to the hospital, and being told to go elsewhere if he didn’t like the low wages. “We were nervous after the shooting in 2010,” he said. “We don’t trust the Chinese anymore: if they could shoot us once, they could shoot us again.”