At least four Yemeni civilians were killed on Tuesday when an bomb exploded in a popular market in the city of Radaa, according to local sources. The sources told Arab Today that an explosive device, planted by militants believed to be linked to al-Qaeda, went off at a night market on Tuesday evening, killing at least four. The explosion comes a day after the bombing of an air force bus in the capital Sanaa that killed at least one officer and wounded several others. Nobody has yet claimed responsibility for Tuesday’s bomb but a security source in the al-Bayda province where Radaa is located told Arab Today that al-Qaeda militants are active in the city.