Thai royal guards of honour stand guard as they celebrate Thai King Bhumibol Adulyadej's 86th birthday near Klai Kangwon Palace, Hua Hin, Prachuap Khiri Khan province, Dec 5, 2013. Thailand's revered King Bhumibol Adulyadej called on his people to do their duty for the security of the country in his birthday address on Thursday but he avoided making direct reference to the latest political turmoil. Thailand's King Bhumibol, the world's longest reigning monarch, celebrates his 86th birthday on Thursday. [Photo/Agencies]