The US embassy in Khartoum Thursday voiced concerns over Sudan`s early release of a man jailed for aiding the prison escape of four men convicted of killing a US diplomat.
"The United States notes with concern the April 5 early release of Qusai al-Jaili, who was convicted as an accomplice in the prison escape of four men sentenced to death," the embassy in Khartoum said.
Jaili helped in the escape of the four killers of John Granville, who worked for the US Agency for International Development (USAID) and was shot with his driver Abdelrahman Abbas in their car on as they returned from a New Year`s Eve celebration in Khartoum in 2008, the statement said.
The four Islamists were convicted of the killings in 2009 and sentenced to death but they escaped from the Kober jail in North Khartoum the following year.
Jaili helped drive the four away but was captured later.
One policeman was killed in the escape.
Sudanese media reported that Jaili was granted a pardon on Tuesday and freed six years into a 12-year sentence, although no reason was given for his early release.
But the Sudanese authorities gave no comment on Jaili`s release and could not be reached to respond to the embassy statement.
The embassy said in its statement that it would "continue to closely follow the details of all who were involved in this act of terror".
"We urge the Government of Sudan, not only to fulfil its previous assurances to hold accountable those involved, but to take all necessary steps to ensure that the murderers, and those who assisted them, will not conduct further acts of violence and terrorism against innocent people.
Two of Granville`s killers remain at large. One was killed in Somalia in 2011 and the fourth was re-arrested and is back in Sudanese custody.
The US State Department is offering a $5 million (4.4 million euro) reward for information leading to the capture of the two killers who are still free.