Amnesty International has condemned a bomb attack in Yemen that reportedly killed at least 17 people and injured 15 as they traveled to celebrate a Shi'a festival in the northern town of al-Zahir. It is unclear who carried out Wednesday's attack. According to media reports, some Yemeni officials suspect al-Qa'ida carried out the bombing. “Whoever carried out this bomb attack appears to have been aiming to inflame tensions in Yemen's conflict-ridden northern regions by inflicting heavy casualties on Zaidi Shi'a festival-goers,” said Philip Luther, Amnesty International's Deputy Director for the Middle East and North Africa. “Such attacks are absolutely prohibited under international law and show a complete disregard for the most fundamental human right, the right to life.” The Zaidi Shi'a belong to a branch of Shi'a Islam that dominates the north of Yemen. According to media reports, the victims were mainly members of the Zaidi Shi'a community, including a provincial tribal leader. Two of the dead were reported as being supporters of the Huthis, an armed Yemeni Zaidi Shi'a group. Huthis, followers of Hussain Badr al-Din al-Huthi in the northern region of Sa'dah, began fighting the government in 2004 in what initially began as a protest at the US-led invasion of Iraq, but developed into an armed conflict, particularly after the killing of their leader by the government. The Yemeni authorities agreed a ceasefire with the Huthis in February 2010. It has held since then despite intermittent reports of breaches. Amnesty