UNITED NATIONS: International peace envoy Lakhdar Brahimi said Friday that a devastating bomb blast in the Syrian capital was a "war crime" that had left about 100 people dead.

The toll given by Brahimi was grimly higher than the 61 dead given by Syrian activists after a suicide bomber staged the attack Thursday near the entrance to President Bashar al-Assad's ruling party offices.

Brahimi said he "strongly condemns the savage and horrible explosion in Damascus yesterday, which resulted in the killing of around 100 and the injuring of two hundred fifty civilians.

"Nothing could justify such horrible actions that amount to war crimes under international law," the UN-Arab League envoy added in a statement.

Brahimi called last month for the UN Security Council to set up an independent international investigation for "such crimes" in Syria.

Assad's government and the opposition have blamed the Damascus attack on "terrorists".