By Tom Gardner

LONDON, Sept 13 (Thomson Reuters Foundation) - Tens of thousands of people in conflict-ridden South Sudan are at risk of dying from starvation with many living in swamps and surviving on water lilies following renewed violence, a senior aid worker has warned.

An estimated 4.8 million people from a population of about 11 million are going hungry with about 40,000 people at risk of dying, said Mercy Corps's South Sudan director Deepmala Mahla.

The hunger crisis comes amid continuing instability and violence in the African country that attained independence from Sudan five years ago with renewed fighting hampering relief supplies.

Here are some key facts and figures about the on-going conflict which is nearly three years long despite a formal peace accord last year, and has resulted in as many as 100,000 deaths and the displacement of 2.5 million people.

* South Sudan attained independence on July 9, 2011, after a referendum in which almost 99 percent of voters chose to become the newest country in the world.

* The new country was plagued with difficulties from the outset. South Sudan possesses enormous oil wealth but little else. Roughly half the population was dependent on food aid.

* Tensions with Sudan in the north stymied the country's progress. The Juba and Khartoum governments argued over border demarcation and oil, leading to a brief war in 2012.

* In December 2013 a full-blown civil war broke out as political in-fighting within the ruling Sudan People's Liberation Movement (SPLM) spilled onto the streets after President Salva Kiir sacked his deputy and long-time rival, Vice-President Riek Machar.

* The ensuing violence was fought broadly between South Sudan's biggest ethnic groups - the Dinka, led by Kiir, and the Nuer, under Machar.

* The conflict took on a regional dimension with Uganda intervening in 2014 on the side of the government in Juba, and Sudan supporting Machar's rebels in the east.

* The U.N. Security Council set up a targeted sanctions regime for South Sudan in March 2015 but has to date not imposed an arms embargo.

* A peace deal signed in August 2015 brought a formal end to the 20-month civil war but fighting in the southern region persisted with over 100,000 displaced.

* But the agreement did enable the return of Machar to Juba and the subsequent formation of the Transitional Government of National Unity in April 2016.

* However in July 2016 fighting flared up in Juba once again, with clashes between forces loyal to Kiir and Machar leaving some 270 dead. A ceasefire was announced four days later, but nearly 103,500 people have fled the capital to Uganda.

* The conflict continues to devastate South Sudanese lives. One in every 5 people in South Sudan have been forced to flee their homes since the conflict began. Nearly 1 in every 3 people were without adequate food in September 2015. Nearly 1 in every 3 schools in South Sudan has been destroyed, damaged, occupied or closed.

* A new report published on Sept. 12 revealed the scale of public corruption, including the private fortunes amassed by politicians in Juba, and suggested the struggle over control of the country's natural resources was a greater driver of conflict than ethnic rivalry.

(Editing by Belinda Goldsmith; (Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking, property rights and climate change. Visit news.trust.org)))