Bangkok: Nine activists who posted comments critical of Thailand’s ruling junta and a military-backed draft constitution on Facebook have been jailed, police said on Saturday, the latest opponents of the government penalised for airing dissent.

The military seized power in May 2014, throwing out an old constitution, clamping down on dissent and promising an election by mid-2017.

But a draft constitution drawn up under military supervision has drawn disapproval from both sides of the political divide, and the junta has responded by banning criticism of the charter in the run-up to an August referendum on it.

Eight activists were detained by the military on Wednesday over Facebook posts criticizing the draft and junta leader Prayuth Chan-ocha. They were charged with sedition, computer crimes and two of them face additional charges of breaking Thailand’s royal defamation law, known as Article 112.

‘The court has approved the first phase of their jail term which will be 12 days,’ Winyat Chatmontree, a lawyer for the group, told Reuters on Friday.

Under the law, suspects can be detained for up to 12 days, extended seven times, before they are formally tried in court.

Demonstrations have been rare since the generals overthrew the government of former Prime Minister Yingluck Shinawatra in May 2014, but a small wave of opposition to the junta and the military-backed charter has arisen in recent weeks.

The junta has appeared increasingly jittery ahead of the Aug. 7 referendum on the constitution, which the country’s two biggest political parties have both criticised as undemocratic.

Opponents say the charter would enshrine military power and would not heal political rivalry that has divided the country for more than a decade.

The military denies seeking indefinite power and says the proposed constitution would heal divisions and usher in stable, corruption-free politics.

At the heart of Thailand’s decade of tumultuous politics has been rivalry between populist political forces that have won huge support in the countryside and the Bangkok-based military-dominated establishment.

In a separate incident, at least 15 people were arrested on Wednesday after they attended small, silent protests in the capital, Bangkok, including one at the Victory Monument, a central landmark and transport hub.

Most were later released but on Saturday the Technology Crime Suppression Division, part of the national police, said it had charged and detained one of the protesters over Facebook posts critical of the military.

‘We have charged him with violating Article 112 and the computer crimes law. He denies breaking both laws,’ Police Lieutenant Colonel Sanpech Noothong told Reuters.

‘He posted comments against the military institution and even though these posts were deleted they are problematic.’

Sunai Phasuk, senior Thailand researcher at Human Rights Watch, said the protests had rattled the military.

‘Their fear tactics worked right after the coup,’ said Sunai. ‘But what they saw at Victory Monument shook their confidence.’