Thai police fire water cannon at pro-democracy protesters

Crowds attempt to hand-deliver letters urging reform of the country's monarchy

Riot police fired water cannon at crowds of Thai pro-democracy protesters as they attempted to reach Bangkok's Grand Palace on Sunday to hand-deliver letters urging reform of the country's powerful monarchy.

Demonstrations have spread across Thailand in recent months, led by young people who have risked lengthy jail sentences to call for the power and wealth of the royal family to be curbed, and for the resignation of the prime minister, Prayuth Chan-ocha.