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Input: The heir to Saudi Arabiaâs throne has accused  Iran  of âdirect military aggressionâ which could be an âact of war â after Saudi air defense forces intercepted a ballistic missile on Saturday fired toward the capital  Riyadh  from across the border in Yemen.
Yemen has been embroiled in a civil war since 2015 between a Saudi-led military coalition in support of the Yemeni government  and Houthi rebels believed to be funded by  Iran .
âThe involvement of  Iran  in supplying missiles to the Houthis is a direct military aggression by the Iranian regime â the Saudi news agency SPA reported  Crown Prince Mohammed Bin Salman  as saying on Monday  âand may be considered an act of war against the Kingdom.â The language closely matched a statement earlier given by the Saudi-led coalition.
 Iran  immediately denied  it  was behind the missile launch.
The head of the Saudi military coalition said that experts in military technology had examined other missiles and âconfirmed the role of  Iran âs regime in manufacturing these missiles and smuggling them to the Houthi militias in Yemen for the purpose of attacking the Kingdom  its people  and vital interests.â
 The crown princeâs  reported remarks mark a new height in tensions between  Iran  and Saudi Arabia  the regionâs rival powers. The civil war in Yemen is widely seen to be a proxy war between the two countries  and has resulted in the deaths of over 10 000 civilians and triggered a humanitarian disaster including a cholera outbreak which has infected nearly a million people.

Saudi Prince Mohammed Bin Salman Condemns Iran ' Act of War'