Syria’s defense minister was among those killed in a suicide bombing in Damascus on Wednesday that targeted National Security headquarters, state television said.Defense minister General Daoud Rajha was one of Syria’s top security officials.The morning attack targeted the regime’s most senior security chiefs, state television said.It happened in the high security Rawda district in the heart of the capital as battles between regime forces and the Free Syrian Army (FSA) raged in Damascus for the fourth consecutive day.Rajha, a Christian, was defense minister, deputy army chief and deputy head of the Council of Ministers. Assad himself is overall commander of the military.In mid-May this year, a reported attempt was made to poison Rajha, and other key regime figures. A delivery boy was said to have added mercury to their food during a meal before fleeing.Rajha was born in 1947. He graduated at the Military Academy in Homs in 1968. He underwent several military courses in the following years. Ever since the protests started in Syria 16 months ago, Rajha believed that his country was exposed to a foreign conspiracy and he often accused the west of making up the chaos in his country.His name came among the list of Syrians hit by European and U.S. sanctions. Western countries considered him one of the main top officials who are responsible for the killings in Syria.Syria appointed General Fahad Jassim al-Freij as defense minister, state television said, to replace, according to Reuters.Freij, who was previously the chief of staff of the armed forces, is from the province of Hama, a center of unrest in the 16-month-old revolt against President Assad.