Residents of rebel-held capital Sanaa told AFP they heard loud explosions and saw plumes of smoke Wednesday after at least a dozen air strikes on the international airport, which is close to an air force base.

The Iranian-backed Huthi rebels said on their Al-Masirah television that the coalition had launched 57 air strikes on Sanaa and their northern stronghold of Saada.

There were no official reports of casualties, but the rebels said a woman and a girl were killed in Saada while a number of children were wounded.

"The operation came in response to the threat of the Huthi militia after they launched ballistic missiles as well as drones from the occupied capital Sanaa, as well as Saada," coalition spokesman Turki al-Maliki told reporters in Riyadh.

"The terrorist leaders of the Huthi militia... will be pursued and held accountable. Targeting civilians and civilian facilities is a red line."

The coalition strike effectively ends a unilateral ceasefire it declared in April, announced as part of efforts to combat the coronavirus pandemic.

Last month, the coalition said it had intercepted and destroyed drones and ballistic missiles launched into the kingdom by the Huthis, including one fired towards Riyadh.

At the venue of Maliki's press conference, Saudi officials displayed remnants of intercepted missiles and drones they said were supplied by Iran to Yemen's Huthi rebels.

Iran denies arming the rebels.

Yemen has been locked in conflict since the Huthis took control of Sanaa in 2014 and went on to seize much of the north.

The crisis escalated when the Saudi-led coalition intervened the following year to support Yemen's internationally-recognised government.

Tens of thousands of people, mostly civilians, have been killed and millions displaced in what the United Nations has called the world's worst humanitarian disaster.

The Arab world's poorest country, already devastated by conflict and malnutrition, Yemen also faces the coronavirus pandemic that its decrepit health system is ill-equipped to handle.

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