Shiite rebels killed 20 people and wounded 70 others in an attack on a Sunni Islamist school in northern Yemen, a tribal sources said on Sunday.
The attack on the Dar al-Hadith school that trains preachers in Dammaj, a suburb of the Shiite stronghold city of Saada, said the tribal source.
Dar al-Hadith, which is attended by students from Yemen and many other countries, is seen as a Sunni threat by Shiite Huthis who dominate the northern region.
A teacher at Dar al-Hadith told AFP on condition of anonymity that Huthis had blocked off the area surrounding the religious school for two weeks, preventing the delivery of food to about 10,000 people.
The reports could not be immediately confirmed.
Tribal sources say that the Huthis have strengthened their hold on Yemen's northern provinces in recent months due to an anti-regime uprising that has seen troops defect and security forces stretched by popular protests.