China said Tuesday it had lodged an official complaint with Myanmar after two soldiers illegally crossed the border into southwest China and shot dead a local resident earlier this year.

It was the first time Beijing has commented on the January 12 incident along the China-Myanmar border in Yunnan province.

Chinese state-run media had made no previous mention of the shooting and it was not clear why Beijing -- a key ally and major investor in Myanmar -- had remained tight-lipped about the incident until now.

"The Chinese side lodged solemn representations with the Myanmar side asking it to find out the truth, punish the perpetrators and compensate the bereaved families," foreign ministry spokesman Liu Weimin told a regular briefing.

"The Myanmar side said it paid attention to the representations and is stepping up investigations."

Kachin News, a Thailand-based website which covers news from Kachin State in northern Myanmar and has close contact with ethnic minority rebels in the area, reported in January that an ethnic Kachin farmer had been shot dead in China.

Lahpai Zau Lawn, 53, "was shot at close range in the abdomen and twice in the head", the report said, citing the man's relatives who live in a village on the Chinese side of the border.

The report said the incident may have been a reprisal after two Myanmar soldiers who crossed the border into China in December in search of food were detained by local villagers and handed to Chinese authorities.

A spokesman for the Myanmar Embassy in Beijing was not immediately available for comment.

Beijing's official confirmation of the shooting came after the China Daily said Tuesday state-owned China Power Investment Corp was pushing Myanmar to restart construction of a $3.6 billion dam in the Southeast Asian nation.

In September Myanmar President Thein Sein ordered a halt to the controversial Myitsone hydropower project, electricity from which is destined for China, following strong public opposition.

The mega dam is located on the Irrawaddy river in Kachin state.

Environmentalists have warned the project would inundate an area about the size of Singapore, submerging dozens of villages, displacing at least 10,000 people and irreversibly damaging one of the world's most biodiverse areas.