The Houthis are an armed political and religious group from northern Yemen which champions the country’s Shia Muslim minority, the Zaidis.

They declare themselves to be part of the Iranian-led “axis of resistance” against Israel, the US and the wider West – along with armed groups such as Hamas and Lebanon’s Hezbollah movement.

Formally known as the Ansar Allah (Partisans of God), the group emerged in the 1990s and takes its name from the movement’s late founder, Hussein al-Houthi. His brother, Abdul Malik al-Houthi, has been its de facto leader since 2004.

In the early 2000s, the Houthis rebelled against Yemen’s long-time authoritarian president Ali Abdullah Saleh. They wanted greater autonomy for the group’s homeland in the north of Yemen. The group seized the capital Sanaa after the 2011 Arab Spring, when a popular uprising forced Saleh to hand power to his deputy.

The Houthis have continued to grow in strength, with troop numbers estimated to have risen to 350,000 last year, and now control between one-quarter and one-third of Yemen’s territory, but 70-80% of its population – about 30 million people.

The group wants an end to a Saudi blockade, control of the whole of Yemen and access to Yemen’s oil and gas revenues.