Syrian state television says a suicide bomber has struck the National Security building in Damascus, killing Defense Minister Daoud Rajha and Deputy Defense Minister Assef Shawkat, brother-in-law to President Bashar al-Assad.

At least one rebel group has claimed responsibility for the attack that seriously wounded several other officials taking part in a high-level meeting Wednesday.

The Syrian government has vowed to “continue fighting terrorism” and has named Armed Forces Chief of Staff Fahed al- Jasem el-Freij as the new defense minister.

This comes amid days of clashes between rebels and government troops in the capital, Damascus.