Cutting off the supply of arms could help increase the chances of a ceasefire holding.
![The ongoing violence is tearing apart South Sudan's cohesion as a nation, writes Copnall [AFP]](https://www.aljazeera.com/wp-content/uploads/2014/05/201443092738681734_20.jpeg?resize=270%2C180&quality=80)

James Copnall is the author of "A Poisonous Thorn in our Hearts" about Sudan and South Sudan after the 2011 split. He was the BBC correspondent for both countries from 2009-12. Before this he was based in Ivory Coast (2004-7) and Morocco (2008-9).
Cutting off the supply of arms could help increase the chances of a ceasefire holding.
![The ongoing violence is tearing apart South Sudan's cohesion as a nation, writes Copnall [AFP]](https://www.aljazeera.com/wp-content/uploads/2014/05/201443092738681734_20.jpeg?resize=270%2C180&quality=80)
What happened in Bentiu is one in a series of massacres stretching back decades into South Sudan’s troubled history.
![Children displaced by fighting in Bor [EPA]](https://www.aljazeera.com/wp-content/uploads/2014/03/2014327233357263734_20.jpeg?resize=270%2C180&quality=80)