The US on Thursday expressed deep concern over a Pakistan court ruling to release the terrorists convicted for the killing of American journalist Daniel Pearl. The Sindh high court has directed release of terrorist Omar Saeed Sheikh and three others who were responsible for the abduction and killing of Pearl in 2002. They are now set to walk free on Saturday. In April, the Sindh High Court had commuted the death sentence of 46-year-old Sheikh to seven years imprisonment. The court also acquitted his three aides who were serving life terms in the case. The US state department has said that it will continue to follow the case closely.