BEIJING China rebuked Myanmar on Thursday and called for an immediate ceasefire between Myanmar government forces and ethnic minority rebels after an artillery shell flew over the border and landed inside China for the second time since late December.
Myanmar's military has stepped up shelling and air attacks on rebels in its northern Kachin state, raising doubts over assurances by its quasi-civilian government that it wants a peace deal to end the fighting that has made its way to China's doorstep.
China's Foreign Ministry spokesman, Hong Lei, said the shell landed 500 metres inside China on Tuesday, close to where Myanmar's military is locked in an 18-month conflict with Kachin Independence Army (KIA) guerrillas.
"China made immediate emergency representations to Myanmar, expressed strong concern and dissatisfaction with the situation, and demanded that Myanmar earnestly investigate and adopt a series of measures to prevent further similar occurrences," Hong told reporters at a regular press briefing.
Hong said no one was injured in the shelling but his comments marked an escalation of China's criticism of Myanmar's government, which is led by former generals who have been praised for reforms after 50 years of strict military rule.
"China calls on both sides involved in the conflict in Myanmar to ... immediately implement a ceasefire ... and jointly protect the peace and stability of the China-Myanmar border area," Hong said.
He did not say which side China thought fired the shell but Myanmar government forces have been using artillery to attack rebels positions on the Myanmar side of the border.
The Foreign Ministry denounced a similar spill-over of the conflict on December 30.
China's state media said last week the government had sent soldiers to the border amid concern that the escalating violence could send refugees spilling over into Chinese territory.
Thousands of Kachin villagers fled into China during earlier phases of the fighting which erupted in 2010 after a 16-year-old truce collapsed.
Kachin rebels, who are fighting for greater autonomy, have come under sustained attack from government forces since late December.
While China has strong business and trade ties with Myanmar, it has long looked with wariness at its poor and unstable southern neighbour and has repeatedly called on it to ensure stability on their log, remote border.
(Reporting by Michael Martina; Editing by Robert Birsel)