Beijing (CNN) — Demonstrators braved a heavy police presence and the threat of arrest by massing Thursday in the streets of Kunming, China, to protest the planned construction of a chemical plant, they said.

“It was mostly a peaceful protest,” said an activist who asked to be identified only by his family name, Young. “We were singing the national anthem, shouting ‘Get out, refinery!’ together.”

He added, “We were scattered by the heavy police force in the area. I saw locals scuffling with police, people getting arrested and pulled away.”

“Every Kunming person cares about this issue,” said another Kunming native, a 50-year-old man who said rows of police thwarted his efforts to reach the heart of the protest. “The police kept blocking off the protest, block by block.”

Local government officials did not respond to CNN phone calls for comment.

Photos posted on Chinese social media sites showed uniformed and riot police surrounding groups of demonstrators.

The five activists who spoke to CNN asked not to be named for fear of reprisals from Chinese authorities.

The oil refinery and chemical plant would be built in Anning city, about 50 kilometers (31 miles) west of Kunming, according to Xinhua, China’s state news agency.

Click here for the full story.