The Southeast Asian Press Alliance says it is “deeply distressed” over suppression of press freedom in Thailand since the army seized power last Thursday.

In a statement it calls for the return of civil liberties and restoration of  freedom of the press, together with steps to “return power to civilian authority based on a popular mandate”.

The statement on Monday followed an order by the National Peace and Order Maintaining Council – which replaces martial law’s Peace and Order Maintaining Command – saying those who commit crimes, face lese majeste charges, undermine security and defy the NPOMC orders will be taken to the military court.

Among those arrested is Thanapol Ewsakul, editor of political magazine Fa Diew Kan (Same Sky). On Sunday, Nation senior reporter Pravit Rojanaphruk gave himself up following broadcasting of a summons the night before. The Bangkok Post reported that Pravit – who was accompanied by a UN human rights representative and lawyers – was subsequently detained and taken to an undisclosed location.

“We urge that he be released immediately,” a SEAPA statement said. “Pravit should not be targeted for doing his job as a reporter and for expressing his views against the martial law and the coup.”

The group says the army also summoned 35 people, mostly academics who spoke out about the monarchy and the reform of lese majeste law, and members of Pheu Thai Party, and including Sondhi Limthongkul who is leader of People’s Alliance for Democracy and the owner of media conglomerate Manager Group. A series of summonses or invitations have called for hundreds to report to the NPOMC, and at least 100 – some estimates put the figure at 200 – were detained.

Since martial law was declared, about 100 web have been blocked, 15 satellite and cable TV stations and an number of community radio stations have been closed. The six free terrestrial and other satellite and cable services closed since Thursday were allowed to resume last Saturday, under strict monitoring by soldiers.

Daily newspapers have been subjected to censorship. Thai media professional groups have urged the NPOMC to review the measures and suggested the junta work with existing media regulatory body the National Broadcasting and Telecom Commission.

Bangkok-based SEAPA says it joins members of the international community who are alarmed about the coup: “We state our unequivocal and fundamental disagreement with a military takeover as a means to resolve the political impasse.

“We call for the release of all persons detained since the declaration of martial law, particularly those from the media. These detentions are arbitrary and illegal – they are being held in the absence of any judicial process, many are in secret locations, and most are not charged of any crime.

“The junta must immediately return civil liberties to the Thai people, restore freedom of the press, and take concrete steps to return power to civilian authority based on a popular mandate.”