An official from the Joint Incident Assessment Team (JIAT), an investigative body set up by the Saudi-led coalition fighting in Yemen, told reporters in the Saudi capital, Riyadh, on Saturday that a probe had found "mistakes" in an August airstrike that killed 40 children on a bus.

He added that those responsible must be "punished."

JIAT legal adviser Mansour Ahmed al-Mansour said the strikes were based on intelligence that indicated the bus was carrying Houthi leaders.

At the time, the Saudis said that the airstrikes had targeted missile launchers used in an attack on the southern Saudi city of Jizan and that the Houthis were using children as human shields.

Read more: Yemen's war explained in 4 key points

The coalition is fighting Iranian-aligned Houthis in Yemen.

Delays in executing the strike after a no-strike order had been issued should be investigated, Mansour said.

"There was a clear delay in preparing the fighter jet at the appropriate time and place, thus losing (the opportunity) to target this bus as a military target in an open area in order to avoid such collateral damage," Mansour said.

International pressure

This follows international pressure to do more to limit civilian casualties in the civil war. A UN panel of human rights experts said last week that some coalition airstrikes may constitute war crimes.

US Secretary of Defense Jim Mattis said last week that US support for the Saudi-led coalition was not unconditional.

Yemen's civil war has been going on for over three years. The coalition backs Yemen's internationally recognized government and aims to restore it to power.

jbh/rc (Reuters, AP, AFP)

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