CAIRO/DUBAI (Reuters) - Yemen's Houthis said on Tuesday they would resume attacks on Israeli ships passing through the Red and Arabian seas, the Bab al-Mandab Strait and the Gulf of Aden, ending a period of relative calm starting in January with the Gaza ceasefire.

Ansar Allah began as a revival movement for Yemen's sizeable Zaidi Shiite Muslim sect in the 1990s and began to grow in size and influence through the turn of the century. The group was headed by Abdul-Malik al-Houthi's elder brother, Hussein al-Houthi, until his death at the hands of Yemeni security forces in 2004.