Thai king's favourite dog dies, after 'insult' arrest

The favourite dog of Thailand's ailing monarch has died, days after a man was arrested under the kingdom's strict royal defamation laws for allegedly making a satirical online remark about the beloved canine.

The dog, called Tongdaeng (Copper), became both a household name and a publishing sensation in Thailand after King Bhumibol Adulyadej adopted her as a stray puppy and penned a heartfelt book about her attributes in 2002.

She was praised for her loyalty and obedience, with the book widely interpreted at the time as a parable about how Thais should live and remember their place within the kingdom's rigid society.

Her death was announced in a statement from the veterinary faculty of Kasetsart University late Monday.

"While Khun Tongdaeng was sleeping and relaxing, she died peacefully on 26 December 2015 at 11:10pm at Klai Kangwon Palace," the statement read.

It said she had been ill for the last few years and was just over 17 years old when she passed away. 

"Khun" is an honorific in Thailand, roughly translating to "ma'am", and was frequently used by officials and local media when referring to Tongdaeng.

Her death was splashed across Thai newspapers Tuesday, with local media reporting that the king had been informed.

The dog regularly featured in palace photographs while the book about her outsold bestsellers such as Harry Potter in Thailand.

A privately funded animated film based around Tongdaeng and her attributes is currently showing at Thai cinemas.

In his book, Bhumibol described Tongdaeng as a "respectful dog, with proper manners" who was "humble and knows protocol".

"She would always sit lower than the king," the book added.