(Reuters) - An al Qaeda splinter group launched a rocket attack on the U.S. embassy in Sanaa on Saturday, injuring several guards, to retaliate for what it said on social media was a U.S. drone strike in a northern province the day before. The rocket landed 200 meters from the heavily fortified embassy, which lies in a compound surrounded by high walls, hitting members of the Yemeni special police force who guard the site. At least two were injured, police said. The attacker fired the rocket from a M72 light anti-tank weapon from a car before speeding away, a police...