Police on Wednesday postponed the first court appearance of 15 arrested pro-election demonstrators until Thursday, to allow further interrogations, amid calls for their immediate release.
The demonstrators were held at Chanasongkhram and Phaya Thai police stations in Bangkok on Tuesday night after being arrested earlier in the day when police stopped a protest march to Government House..
Supporters and relatives expected police to take the detained demonstrators to the Criminal Court on Wednesday morning and ask for permission to further detain them in custody, when they could also seek court bail.
Pol Maj Gen Senit Samransamruankit, commander of metropolitan police subdivision 1, said on Wednesday that police had not yet finished interrogating them, and would exercise theright to detain them for 48 hours.
He expected police would take the detainees to court at 10am on Thursday.
The demonstrators were charged with violations of the public gathering law, sedition, creating disorder, refusal to end their gathering, violating the ban on political gatherings issued by the National Council for Peace and Order, and blocking traffic.
The demonstration started at Thammasat University's Tha Phra Chan campus on Monday evening and ended Tuesday afternoon when security authorities prevented them marching from the campus to Government House. Some demonstration leaders were arrested and others surrendered.
Tuesday marked the fourth anniversary of the NCPO's coup-backed seizure of power. Demonstrators demanded the general election be held this November, as earlier scheduled, and the NCPO be dissolved. The promised polls have been postponed several times in the last four years, and are now promised for "early 2019, no sooner".
Anusorn Iamsa-ad, acting spokesman of the Pheu Thai Party, said the NCPO should not take legal action against the demonstrators because they fought for a democratic election, which was a basic right, and they posed no harm to national security.
The Southeast Asian office of the United Nations High Commissioner for Human Rights demanded the immediate release of the demonstrators and some activists vowed to stage another rally to demand their release.
Pitikan Sithidej, director-general of the Rights and Liberties Protection Department, urged the United Nations office to respect Thai laws. She said police pressed charges against the demonstrators in accordance with the law, and their cases were being handled by the justice system.
The demonstrators had already exercised their legal right by seeking the Administrative Court's permission for their march, but the court rejected their petition, she said.
All parties involved should show respect for other people's rights and the benefits of co-existence, she said.
The management of Thammasat University announced on Wednesday that it would not file a police complaint against the demonstrators who broke into its campus on Monday, because it was a trivial issue.