Prime Minister Prayut Chan-o-cha has threatened to summon any critics of the regime who disrupt its efforts to restore peace in Thai politics.
The Nation senior reporter Pravit Rojanaphruk was the latest government detractor to be summoned and held on Sunday after reporting to the 1st Army that afternoon.
Dismissing calls for the National Council for Peace and Order (NCPO) to stop detaining critics, the premier insisted yesterday that a person would "have to face [summonses] if they defame [the government and the NCPO]".
Pheu Thai secretary-general Phumtham Wechayachai is among those likely to be summoned next. He has criticised the coup-makers for detaining those who disparage the military for what it calls "attitude adjustment".
"I don't understand why they keep talking [that way] while the nation is moving forwards," Gen Prayut said.
He said he was aware that people, particularly politicians and media, have the right to take the government to task, but stressed that this was not the right time. Gen Prayut added that some critics seemed to care more about expressing their political opinions than healing a deeply divided society. "The political stuff should be dealt with in the future," he said.
The media has criticised the NCPO for harming press freedom by detaining Pravit. Manop Thip-osod, Thai Journalists Association (TJA) deputy president for media freedom and reform, said it was normal for journalists like Pravit to criticise the government.
He criticised authorities for wielding their power against those with different opinions in "an act that is not suitable to the current situation of the country".
The TJA and the Foreign Correspondents' Club of Thailand have backed The Nation's call to release Pravit.
Thepchai Yong, editor-in-chief of the Nation Multimedia Group, the publisher of The Nation, said "authorities gave no clear reason why he [Pravit] was detained" and were acting to intimidate media and restrict press freedom. He added that if the reporter had broken the law, authorities should act against him using the usual legal channels.
Pravit is known for his views opposing the military, which he has mentioned several times on social media. His last tweet at 2pm on Sunday read: "Freedom can't be maintained if we're not willing to defend it."
Last year he was summoned and detained at the 1st Development Division in Ratchaburi for seven days.
NCPO spokesman Winthai Suvaree said he was unable to confirm how long Pravit would be held as it would depend on his cooperation and the results of the authority's probe into his actions. Authorities found Pravit's recent comments referred to some people and organisations in a way that could "cause confusion in society", Col Winthai said.
Meanwhile, the 2nd Division commander Maj Gen Sisak Phunprasit said Sgt Witsanuphong Khonphian had nothing to do with the assault on former Pheu Thai MP Wattana Muangsuk. The commander said the sergeant was at Muang Thong Thani football pitch last Saturday to watch sports and had no idea who Mr Wattana was.
Mr Wattana had complained of being attacked by a man after playing football. He said he noticed a military officer, who he referred to as a sergeant, near the spot.