A leading member of the Thai red shirt movement who fled the country after bloody protests last year surrendered to the authorities on Wednesday in a case that could increase tension between the government and critics.
Arisman Pongruengrong, who is thought to have been living in Cambodia, had faced a series of charges including invading parliament, terrorism and the theft of military ammunition.
After his surrender, the Criminal Court said it would pursue the charge of terrorism related to events during the protests in 2010 and denied him bail. Other charges could be pursued later.
The reason the court did not grant bail was due to the fact there was a warrant for his arrest and he evaded it for a long period of time before turning himself in, Suthem Srisoda, Arisman's lawyer, told reporters.
They're afraid that if they grant him bail this time, he may evade the law again.
At least 91 people died in protests in April and May last year when the red shirts, formally known as the United Front for Democracy against Dictatorship, were trying to force former Prime Minister Abhisit Vejjajiva from power.
Abhisit prevailed then, with the military ending the protests in a bloody crackdown. But his Democrat Party was thrashed in a general election in July this year by the Puea Thai Party and Yingluck Shinawatra became prime minister.
She is the sister of ex-premier Thaksin Shinawatra, the figurehead of the red shirt movement who was toppled by the military in 2006 and now lives in exile to avoid a prison term for abuse of power.
Arisman is considered a hardliner in the red shirt movement and any sign that he is being treated leniently by the judicial system could provoke a backlash among opponents of Thaksin and the current government.
The royalist, nationalist yellow shirt movement, whose huge street rallies helped undermine Thaksin and governments allied to him, has already threatened protests if Thaksin is allowed to return home without having to serve time in jail.
Earlier, around 100 red shirt supporters cheered when Arisman arrived at the Department of Special Investigation, the Thai equivalent of the U.S. Federal Bureau of Investigation.
He told reporters he had more confidence in the justice system now so he had decided to turn himself in. I think the situation has eased ... I deny all the charges, he said.
In July, several red shirt leaders also won seats in parliament as Puea Thai candidates.
But one of these lawmakers, Jatuporn Prompan, was disqualified last month by the Election Commission.
He was remanded in prison at the time of the election on terrorism charges and the Election Commission said that made him ineligible to stand for Puea Thai under the party's own rules.
Puea Thai says it had changed its rules but the Commission does not accept that. The Constitutional Court will have the final say on the decision to exclude him from parliament.
(Reporting by Jutarat Skulpichetrat, Panarat Thepgumpanat and Aukkarapon Niyomyat; Writing by Alan Raybould; Editing by Yoko Nishikawa)