(Reuters) – An Islamist militant group claimed responsibility on Thursday for an attack on the Syrian army headquarters in Damascus a day earlier, according to a statement posted on the Internet.

The Al Nusra Front said Wednesday’s assault was carried out in two stages, starting with a suicide bomber detonating a car near the building.

It said four suicide attackers posing as security guards entered the compound in a second vehicle, seized the first floor and engaged soldiers inside before detonating their car, setting the building on fire.

The statement, which featured photos of the building on fire, said all five militants died in the attack.