The Houthi rebels of Yemen said Sunday they had fired a ballistic missile at a nuclear power plant in Abu Dhabi, targeting the second member of the Arab coalition battling them, after Saudi Arabia. There was no independent confirmation of the claim. Last month, the Houthis fired an Iranian-supplied missile at the international airport of Riyadh. It was intercepted by Saudi air defenses. The Yemeni rebels apparently aimed at a nuclear power plant which is still under construction on the UAE’s Gulf coast in which $20bn is invested. It won’t be finished before the end of 2018.