AMMAN - The Syrian military said it would extend a nationwide ceasefire for another 72 hours from Tuesday, state media reported on Monday. The military high command said in a statement reported by state media that 'a regime of calm will be extended for a period of 72 hours from one o'clock on July 12.' The Syrian government uses the term 'regime of calm' to denote a temporary ceasefire. The Syrian army and the Russian military, which backs Syrian President Bashar Assad, have periodically announced a temporary local truces in areas of intense fighting. Air strikes and fighting have often continued in spite of the declarations