* Anti-coup protest leaders had refused to turn himself in
* Junta appeals again to international community for time
* Says absolute power needed to solve problems quickly
* Military took over in May saying needed to restore order (Adds comment from junta leader during TV address)
By Amy Sawitta Lefevre
BANGKOK, June 6 (Reuters) - Thai security forces tracked down and detained a prominent activist who helped organise protests against last month's military coup from comments he posted on the Internet, officials said on Friday.
Sombat Boonngamanong was caught in Chonburi province east of Bangkok late on Thursday, traced via the Internet network he was using, said Major General Pisit Pao-in, of the Information and Communication Technology Ministry.
"Soldiers and police were informed of the IP address used by Sombat to post comments so we searched a house in Chonburi and found Sombat there. We detained him. He is now with the army at an army base in Chonburi," Pisit told Reuters.
"The case is now with the army and it will investigate and decide how to proceed next."
The military has cracked down hard on pro-democracy dissidents and supporters of ousted Prime Minister Yingluck Shinawatra since it took power last month.
Yingluck, her ministers and prominent supporters of the Shinawatras have been detained, most for brief periods, and warned against anti-military activity. The military has not said how many people are being kept in custody.
The royalist establishment, dominated by the military and old-money elite, has been in conflict for a decade with supporters of Yingluck and her brother Thaksin Shinawatra, who are adored by the poor. Thaksin was ousted in a coup in 2006.
Yingluck was prime minister until May 7, when a court found her guilty of abuse of power and she stepped down. The army toppled the remnants of her government on May 22, saying it needed to restore order after six months of violent protests that had brought the economy close to recession.
Since then the junta has moved to suppress criticism and nip protests in the bud.
Sombat, who had refused to turn himself in to the military authorities after being summoned, managed to post a final status update on Facebook saying: "I have been arrested."
He had helped organise protests via social media in defiance of the junta's ban on political gatherings of more than five people. He had previously organised regular demonstrations to mark a crackdown by the army on pro-Thaksin "red shirts" in May 2010 that ended a protest at which more than 90 people died.
Last Sunday, the ruling military council sent 5,700 troops and police into central Bangkok to stop anti-coup protests as soon as they sprang up. Most were small events held around shopping malls. Very few protests have been seen this week.
Prayuth told Chinese businessmen in Bangkok on Friday that an interim government would be set up in three months' time and asked that they continue investing in the country.
In a televised address to the nation, also on Friday, he reiterated a call for patience from the international community as his military government worked to reform the country.
"We ask for time... to build a true democracy with discipline," he said. "I understand it is dangerous to use absolute power to solve problems, but these problems must be solved as soon as possible."
The United States has urged Prayuth to call elections quickly, release detainees and end censorship. Prayuth has said it will take at least a year to engineer reforms before a vote.
He called on government agencies to work swiftly to regain the confidence of the international community. His remarks appeared less rehearsed than in a previous address last week.
Former Education Minister Chaturon Chaisang was taken to a military court in brown prison garb and handcuffs on Friday so the authorities could extend his detention after he failed to turn himself in when summoned, but he was granted bail.
The army says he had posted information online that was inaccurate and misled foreign media. He was arrested in Bangkok on May 27 at the Foreign Correspondents' Club of Thailand and bundled away by soldiers after addressing journalists.
The army has detained politicians, journalists and academics on both sides of the political divide, but a disproportionate number are Thaksin's supporters.
On Wednesday, it summoned a further 21 people, including red shirt founding member Jakrapob Penkair, a former minister in a pro-Thaksin government who was forced to resign in 2008 after being accused of violating Thailand's strict lese-majeste laws.
He now lives in neighbouring Cambodia and said this week he would help organise a campaign of civil disobedience to military rule with others allied to the ousted government.
Thaksin himself fled abroad in 2008 to escape a jail sentence for abuse of power and is based in Dubai. He has made little comment since the coup.
The National Anti-Corruption Commission said on Thursday it had launched a probe into the assets of Yingluck and four other ex-ministers related to a rice-buying scheme that helped undermine her government as farmers went unpaid for months.
If found to have profited from the scheme, all five could have their assets seized.
Yingluck was seen in public on Friday for the first time since the coup, walking around the recently opened, high-end Central Embassy shopping mall in Bangkok.
The country has been mostly calm since the coup. A curfew remains in force from midnight to 4 a.m. across most of Thailand, although the junta has lifted the curfew in some tourist areas this week. On Friday it said a curfew was no longer in place in two districts and provinces including the popular beach resort of Krabi.
Thailand's Commerce Ministry said on Friday that prices of many consumer goods would be capped for six months to November to hold down living costs and boost the economy and confidence.
"Producers of 205 categories of necessary consumer goods are happy to freeze prices for six months," the ministry's permanent secretary, Srirat Rastapana said in a statement after meeting with companies and trade associations. (Additional reporting by Aukkarapon Niyomyat and Panarat Thepgumpanat; Writing by Alan Raybould and Simon Webb; Editing by Louise Ireland)