Around 500 people including dozens of Buddhist monks protested near the Chinese consulate in Myanmar's central city of Mandalay on Saturday demanding the closure of a flashpoint copper mine.
It was the largest protest since the fatal shooting of a woman demonstrating against the Letpadaung mine in the northwestern town of Monywa -- a Chinese backed venture dogged by complaints of land grabbing and environmental damage.
Khin Win, in her 50s, was killed last Monday when police opened fire on protesters trying to stop the mine company building a fence in territory disputed with local farmers.
The mine -- run by Chinese firm Wanbao as part of a joint venture with a major local military conglomerate --- has raised questions about Myanmar's reliance on investment from neighbouring China, which gave crucial political support to the former junta.
"We want the truth of what happened in Letpadaung as Khin Win was killed. We want the authorities to take appropriate action," Thein Aung Myint, a protest organiser from Movement for Democracy Current Force (MDCF) told AFP.
Small but near-daily protests against Wanbao have been held in Yangon and Mandalay.
"We are not against China. We are neighbours. But we are worried that relations between China and Myanmar may be damaged," by the mine dispute, Thein Aung Myint added.
Mandalay police confirmed the protest, saying hundreds were in attendance but no arrests were made.
Keen to prevent the issue snowballing, Wanbao has recognised the woman's "senseless death" as "painful and poignant", while China's foreign ministry on Wednesday also expressed its regret.
The Letpadaung copper mine has triggered several rounds of fierce opposition from local villagers.
In November 2012 a botched police raid using phosphorus on a protest at the mine left dozens of people, including monks, with burn injuries.
That crackdown, the harshest since the end of outright army rule in 2011, sparked fury in the Buddhist-majority country.
Earlier this year two Chinese workers were kidnapped at the site by activists, though they were later released unharmed.
A new quasi-civilian government has implemented headline-grabbing reforms in recent years, including releasing political prisoners and allowing opposition leader Aung San Suu Kyi into parliament.
But land disputes and battles for nation's rich mineral resources are posing an increasingly serious challenge.
Wanbao on Monday said Myanmar would receive $140 million a year in tax from the project.
In July 2013 the country revised the terms of the mine deal with Wanbao, giving the nation a share of the profits in an apparent attempt to allay public anger.