Thailand and Cambodia exchanged heavy artillery fire for a second day on Friday as their worst fighting in over a decade intensified and spread to new areas, despite international calls for a ceasefire.

Thailand claims the ordnance was newly laid, but Cambodia says they are leftovers from a final stint of fighting during the murderous Khmer Rouge regime. Still, soon after the incident, both sides downgraded relations, expelled their neighbour’s ambassador and recalled embassy staff.

If Cambodia could solidify its territorial holdings in this war, it could not only enhance its own geopolitical and geoeconomic power, but also expand China’s influence.