(ABC NEWS) A suicide bomber at Syria’s national security building has killed the country’s defense minister and the Syrian president’s brother-in-law, and wounded other senior officials, Syrian state-run TV said.

Defense Minister Dawoud Rajha, 65, died in the attack today after four days of battles in which Syrian troops used tanks and helicopters against rebels. Rajha is the most senior official to die during the country’s civil war, which has escalated since the spring of 2011.

The country’s 62-year-old Deputy Defense Minister Assef Shawkat, who is Syrian president Bashar al-Assad’s brother-in-law and a top aide, also died in the attack, according to Syrian State TV.

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