Two Thai high school student leaders will be charged for joining a banned protest last month, police said on Friday, a day after embattled Prime Minister Prayuth Chan-ocha threatened tougher action against protesters.

The students said they had been summoned for violating an emergency decree by joining a protest on Oct 15, when tens of thousands of people defied a ban by Prayuth aimed at halting protests demanding his removal and reforms of the monarchy.