* Over 6,000 troops, police prepared for deployment
* Focus on five sites including airport, Grand Palace
* Coup leader declares himself head of investment body
By Apornrath Phoonphongphiphat and Panarat Thepgumpanat
BANGKOK, June 8 (Reuters) - Thailand's junta has prepared a force of over 6,000 troops and police for deployment in Bangkok on Sunday to smother protests and prevent opposition to the May 22 coup from gaining momentum.
The military has cracked down hard on pro-democracy dissidents and supporters since it ousted Prime Minister Yingluck Shinawatra last month, seeking to mute criticism and nip protests in the bud.
A heavy security force presence at potential flashpoints in Thailand's largest cities since the coup has limited protesters to small gatherings, which are often coordinated through social media and mostly located around shopping malls.
Authorities were focusing on five possible protest sites in Bangkok on Sunday, said deputy police chief Somyot Poompanmoung.
They included the country's main international airport and the downtown area around the Grand Palace, as well as sites where protests have previously taken place, he said. The palace is one of Bangkok's top tourist attractions.
"We hope the protests would not ignite any violence and would end peacefully," Somyot said.
Army chief and coup leader General Prayuth Chan-ocha had instructed security forces to avoid confrontation, Somyot said. Police would photograph protesters, identify them and issue arrest warrants later, he said.
The force on Sunday numbered 27 army companies and 15 police companies, Somyot said. A similar number of troops and soldiers were deployed a week ago.
Thailand's May military coup was the latest convulsion in a decade-long conflict between the Bangkok-based royalist establishment and the rural-based supporters of Yingluck and her brother, former prime minister Thaksin Shinawatra.
Thaksin, who was ousted in a 2006 coup and has lived in self-exile since a 2008 corruption conviction, won the loyalty of the rural poor with populist policies and was the real power behind the deposed government of his sister.
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 sometimes violent anti-government protests that had brought the economy to the brink of recession.
Thailand has been without a properly functioning government since December, when Yingluck dissolved parliament and called a February election in a bid to end anti-government protests. But protesters disrupted the vote, the election was annulled, and Yingluck's crippled caretaker government was forced to limp on.
COUP LEADER HEADS INVESTMENT BOARD
The military has moved swiftly to revive the economy, and has given itself two months to clear a backlog of applications from local and foreign investors to spend more than $21 billion on projects in Thailand.
The backlog arose because Yingluck's caretaker government lacked the power to appoint a new team to run the Board of Investment to replace executives whose term ended in October.
Prayuth on Saturday declared himself the head of the body considering the investment applications, a position typically held by the prime minister.
Quick approval would bring longer-term stimulus to the economy and follow the payment of billions of dollars in subsidy arrears to rice farmers that has already lifted consumer sentiment.
The military's move to pay debts to farmers quickly after seizing power on May 22 contributed to the first rise in consumer sentiment in 14 months in May. Political turmoil had sunk consumers confidence to a 12-month low in April. (Writing by Simon Webb; Editing by Michael Perry)