China expressed concern on Wednesday about a protest against a Chinese-run copper mine in Myanmar in which a person was killed and some were wounded saying China urged its companies abroad to act responsibly and protect the environment.

Myanmar police on Monday fired on protesters near the Letpadaung mine which is at the center of a long-running land dispute, killing one person and wounding 20.

The mining company, Myanmar Winbao, is a unit of the Chinese weapons manufacturer China North Industries Group Corp.

"We express concern and regret at the reports of casualties. We call for the relevant parties to appropriately deal with those victims' cases," Chinese Foreign Ministry spokeswoman Hua Chunying told a daily news briefing.

She said China and Myanmar were friendly neighbors and their "cooperation fits the common interests of both sides".

"China's government has consistently required Chinese enterprises with investments abroad to respect other countries' laws and regulations, exercise social responsibility, and place importance on protecting the environment," she said.

Residents have protested against the Letpadaung mine in Monywa, about 100 km (60 miles) west of Mandalay, saying thousands of acres of land have been confiscated to enable the project to proceed.

In November, human rights group Amnesty International urged the Myanmar government to halt work at the site, saying land had been acquired through a flawed process and other social and environmental issues had to be resolved.

The group also said authorities had yet to be held accountable for attacks on protesters two years earlier. In November 2012, more than 100 people including at least 67 monks were hurt when riot police raided protest camps.

Twin Chinese oil and gas pipelines across Myanmar have also sparked controversy, as have China's interests in hydropower schemes.

In 2011, Myanmar President Thein Sein suspended the $3.6 billion, Chinese-led Myitsone dam project, some 90 percent of whose power would have gone to China, angering Beijing.