Yemen detainees ?suffer abuses? Pro-government militiamen and Houthi rebels have committed serious abuses against detainees in Yemen's second city Aden, Human Rights Watch says.The US-based group alleges southern militias have summarily killed at least seven Houthi prisoners since March.In one case, a rebel was beaten in a public square before being shot dead.The rebels are accused of unlawfully detaining and mistreating civilians before they were driven out of Aden in July after months of fierce fighting.