A man lobbed a grenade in a busy market on Friday in Yemen\'s second city Taez, killing at least six people, officials said, while a blast in the capital Sanaa claimed one more life. Ten others were injured in the attack in Taez, staged when the market re-opened in the evening after the daily fast for the Muslim month of Ramadan, an official in the Taez governor\'s office said. \"A man on a motorbike threw a grenade, killing six people and injuring 10 others,\" he said, adding that the motive behind the attack was not yet clear. Another person was killed and one more was injured in a blast in a southern neighbourhood of Sanaa when an explosive device placed near an Internet cafe went off, locals and a doctor said. The defence ministry said the explosion occurred near a khat market. Khat is a plant chewed for its stimulant qualities and is banned from import to the United States and many European countries, though it is still legal in Britain. Taez was a protest hotbed last year during months of unrest against the rule of former president Ali Abdullah Saleh, who stepped down in February after 33 years in power.