China says its neighbor and close ally North Korea has expressed its grief following the fatal shooting of three Chinese nationals on the countries' border last week. A Chinese Foreign Ministry spokesman said Thursday both countries were investigating the case. The shootings have put further strain on the relationship between Beijing and Pyongyang following the sinking of a South Korean naval vessel by a North Korean submarine.
Chinese Foreign Ministry Spokesman Qin Gang says relevant authorities from both countries have launched an investigation into the case.
China earlier made a rare formal public complaint about its neighbor and the killings of three Chinese nationals and the wounding of another.
State media said Thursday Pyongyang vowed to prevent any repeat of shootings, which it said were "accidents." It also said Pyongyang had expressed grief over the deaths.
North Korea wants to smooth over the incident as China is its sole major economic and political ally. China says North Korea has promised to severely punish the guards responsible for the shooting deaths.
Relations are already under strain as Beijing struggles to remain neutral over the torpedoing a South Korean naval ship in late March, killing 46 sailors. Seoul and the international community blames North Korea for the sinking.
The three killed and one wounded in the border incident were apparently mistaken for smugglers according to the Chinese Foreign Ministry.
China's 1,416 kilometer border with North Korea is guarded by troops on both sides. The river dividing the two countries is often narrow, shallow and accessible to smugglers and refugees passing from the North into China.