In Philippines, at least 13 marines were killed and 40 others injured in fierce fighting with Muslim militants who have laid siege to southern Marawi city for nearly a month in the biggest single-day loss for government forces. <br/><br/>Lt Colone Jo-ar Herrera, spokesman for the Philippine army said the marines were conducting a house-to-house search for militants allied with the Islamic State group who are still occupying parts of Marawi when the battle erupted. He said that about 30-40 militants used civilians as human shields, making it hard for troops to operate, and also positioned themselves in the city's many mosques.<br/><br/>Philippine President Rodrigo Duterte has declared martial law in the Mindanao region, the southern third of the Philippines and home to a decades-long Muslim separatist rebellion.