Amnesty International said it has damning evidence of war crimes by the Saudi Arabia-led coalition on Yemeni civilians, which depends on the United States for some of its arsenal.

In a report released on Wednesday (October 7), Amnesty said the U.S. should immediately stop selling weapons to the Saudi coalition and accused Washington of being complicit in potential war crimes if it continued to supply arms which are used to target civilians.

An expended BLU-108 canister from a CBU-105 Sensor Fuzed Weapon found in the al-Amar area of al-Safraa, Saada governorate, in northern Yemen on April 17, 2015. (Image from http://www.hrw.org)

She was part of a fact-finding mission to Yemen in June and July this year who documented 13 deadly air strike attacks which killed more than 100 civilians, including 59 children.

The report said there is a pattern of disregard for civilian lives, with homes, schools and mosques targeted.

Some were bombed several times, suggesting they were the intended targets despite no evidence they were being used for military purposes, Amnesty said.

She acknowledged it will be hard to persuade staunch Saudi ally, Washington, to suspend arms sales to the Kingdom.

She said if Washington continues to sell weapons and military hardware to the Saudi-coalition in light of the report's evidence the U.S. will be "complicit" in future war crimes.

Amnesty said Saudi bombing Yemen with impunity only serves to fan the flames of violence in the region - on all sides.

Amnesty researchers also found evidence of cluster bombs being used in Yemen, which are banned under international law. The report said that more civilians have died as a result of coalition air strikes than from any other cause during the Yemen conflict.

In 3 May 2015 according Human Rights Watch the Saudi Arabia-led coalition using US-supplied cluster munitions in its airstrikes on Houthi forces in Yemen. Targets include those close to villages, posing a threat from undetonated sub munitions to civilians.