Tehran vowed to carry out revenge attacks against Israel on Saturday after a missile strike flattened a building used as a base of Iran's elite Revolutionary Guards in Damascus, killing five Guards and an unspecified number of Syrian troops.

Ambulances and fire trucks gathered around the site of the strike, which had been cordoned off, a Reuters journalist at the scene said. Rescue operations for people stuck under the rubble continued through the day. A crane was in place to hoist concrete slabs off the wreckage.