Otieno says residents never really recovered from tribal clashes that followed the 2007 presidential elections which saw over 1,000 killed nationwide.
"During the violence, many landlords lost control over their shanties and have since been unable to collect rent from the tenants. Those who held on tightly to their property will not let go."
But for all the recent tensions, the battle to register Kibera as Nubian land is not new.
"It began in 1938," said Diab. "Since independence, Kibera has been contested land."
Although in 1971 parliament passed a bill requiring the government to demarcate and issue titled deeds to Kibera's rightful owners, the plan was never carried out.
In 2009, the government began a resettlement scheme to relocate Kibera residents from the slum into houses that the government had built not far from the slum, but the project was met with similar controversy and resistance.