Brother of groom fired shots in celebration at Riyadh palace . Caught on horseback as he loses sight of the powerful crowd at wedding . Guests rushed for cover as a hail of bullets ricocheted off the roof .
Brother of groom fired Kalashnikov in celebration at Riyadh reception . Caught on camera as he loses control of the powerful rifle at wedding . Guests dived for cover as a hail of bullets ricocheted off the walls .