Thai authorities have issued arrest warrants for six activists who took part in a demonstration at which students called for reform of the country’s powerful monarchy, police have confirmed.

Last week, at a rally attended by thousands, students risked lengthy jail sentences by reading a 10-point manifesto for reforming the monarchy, including a proposal to scrap strict laws that ban criticism of the king. Such comments were, until recently, highly unusual, and shocked many in the country.

The charges against the six protesters do not relate to their demands, but are for breaching internal security and coronavirus measures that have banned public gatherings, as well as computer crimes. Three of those targeted have already been arrested once and bailed over recent protests.

Thailand has some of the strictest lèse-majesté (offending the monarchy) laws in the world, and anyone who “defames, insults or threatens the king, queen, heir-apparent or regent” can face up to 15 years in jail. Prime minister, Prayuth Chan-ocha, who first came to power in the 2014 coup, has said that the king had requested no prosecutions under the laws for now.

The six include Panusaya Sithijirawattankul, 21, the student who read out a list of proposals to reform the monarchy. They also include Anon Nampa, who made the first public call for royal reform at a Harry Potter themed protest.

“They can hand themselves in today or whenever but shouldn’t bring a crowd,” Police Lieutenant General Amphol Buarabporn told Reuters. “If they don’t hand themselves in, we can arrest them when they’re spotted.”

Pro-democracy protests led by students have swept across the country, with rallies taking place on an almost daily basis for more than one month. Their three demands are: dissolve parliament, end the intimidation of activists and rewrite the constitution, which was written under military rule and has cemented the army’s power.

Some students have also called for reforms to curb the powers of King Maha Vajiralongkorn over the constitution, the armed forces and the palace fortune – breaching a longstanding taboo.

In addition to the arrest warrants issued against protesters, the ministry of digital economy and society said on Wednesday that it will also file a complaint against exiled academic Pavin Chachavalpongpun for creating a Facebook group deemed critical of the monarchy, ministry spokesman Putchapong Nodthaisong.

The group, called Royalist Marketplace, has more than 1 million members.

Prayuth has said that young people have the right to protest, and that would listen to their concerns regarding the constitution. However, he has said the rally at which the calls for royal reform was made “went too far”.