Thailand's King Bhumibol Adulyadej
Celebrations started with a morning religious ceremony on June 9 involving 770 Buddhist monks, a figure seen as auspicious.

Thais on the day celebrated their king’s 70 years on the throne by wearing yellow and hanging the king’s portrait everywhere in the public.

King Bhumibol, the world's longest-reigning monarch, is one of the most beloved kings in the Thai history thanks to more than 2,000 projects and initiatives to improve living standards of the poor.

The king underwent a heart surgery on June 7 and the medical team is closely monitoring him. He has not been seen in the public for months.