An international rights group says the Saudi-led coalition waging an air campaign against Yemen’s Houthi rebels in the north are killing children in what amounts to war crimes.

Human Rights Watch released a study on Tuesday documenting the deaths of 26 children killed in five airstrikes since June.

The group said that despite promises by the coalition to abide by international law, the airstrikes have failed to do that and urged the United Nations to again place the coalition on its “list of shame.”

HRW also called for an international investigation into possible war crimes.

The UN’s annual report showed that 785 children were killed and more than 1,000 others wounded in Yemen in 2015, with 60 % of the casualties caused by coalition airstrikes.