Abdel Raouf Abu Zeid, in his 30s, was released on Monday after Khartoum agreed to pay compensation to Washington.
The US State Department said on Wednesday that Washington was deeply concerned about the release of a Sudanese man sentenced to death for the murder of a US diplomat in 2008.
Abdel Raouf Abu Zeid, in his 30s, was released on Monday after Khartoum agreed to pay restitution to Washington, according to his lawyer.
He was sentenced to death along with three other men for shooting dead John Granville, who worked for the US Agency for International Development (USAID), and his driver Abdelrahman Abbas Rahama.
The four convicts had managed to escape in 2010 by digging a tunnel, killing one police officer and injuring another. Mr Abu Zeid was caught, one of his co-detainees is still at large and the other two are presumed dead in Somalia in 2011.
The claim that Abdelraouf Abuzeid’s release was agreed to by the US government is inaccurate, State Department spokesman Ned Price said in a statement. He added that Washington is deeply troubled by the lack of transparency in the legal process that led to his release.