Factbox: South Sudan - the world's youngest country torn by conflict

LONDON (Thomson Reuters Foundation) - As the conflict in South Sudan enters its fifth year, half of the country’s 12 million population needs aid to cope with the effects of war, hunger and economic decline.

The conflict, which erupted two years after the country won independence from Sudan, was sparked by a feud between President Salva Kiir and his former deputy Riek Machar. Fighting has raged mostly along ethnic lines.

On Wednesday South Sudan and the United Nations appealed for $1.7 billion to help avert starvation amid the civil war, but aid groups said bureaucracy, violence and soaring fees were preventing them from reaching those in need.

Here are some facts about the conflict in the world’s youngest country:

** About 4 million South Sudanese have been forced to flee their homes. Nearly 1.9 million are internally displaced and about 2.1 million have fled to neighboring countries.

** Up to 85 percent of internally displaced are women and children.

** Nearly 5 million people are severely food insecure. Earlier this year, pockets of the country plunged briefly into famine.

** The fighting has killed tens of thousands of people since it started in late 2013.

** Only 22 percent of South Sudan health facilities are fully operational.

** Some 900,000 children suffer from psychological distress and 2 million are out of school.

** More than 19,000 children have been forcibly recruited by armed groups.

** The cost of living in South Sudan has increased sharply, with inflation in the capital Juba reaching 183 percent year-on-year.

** Some 28 aid workers have been killed in South Sudan this year. Nine were shot dead in November.

Sources: Reuters, UNICEF, UN OCHA.