Ammon News - JUBA (AFP) - South Sudan is guilty of widespread human rights abuses and awash with corruption, campaigners warned on the second anniversary of the country's independence Tuesday.

US activists who backed the split from Sudan claimed in a letter that the fledgling country faces "an increasingly perilous state".

Signatories of the letter, which accuses the new country of failing its own people and repeating the mistakes of previous rulers before independence, include John Prendergast, a former director for African affairs at the White House's National Security Council.

"Many people in South Sudan are suffering, yet government officials seem to care only about themselves," reads the letter, also signed by former US State Department officials including Ted Dagne, a former advisor to the government.

"We joined you in your fight against these very abuses by the Khartoum regime for many years," they wrote in the letter, which is addressed to South Sudan's President Salva Kiir.

"We cannot turn a blind eye when yesterday's victims become today's perpetrators," they said.

The activists, who call themselves the "Friends of South Sudan", also said there was "clear evidence of massive corruption" and urged "profound reform".

South Sudan split from Sudan on July 9, 2011, after its people voted overwhelmingly for independence in a referendum six months earlier, part of a 2005 peace deal that ended one of Africa's longest civil wars.